Reaction time is the time it takes for a driver to recognize a hazardous situation and initiate a response, such as braking or steering. It is one component of the total stopping distance of a vehicle. The other components of stopping distance include the distance traveled during the period of reaction time (the distance the vehicle travels before the driver begins braking) and the braking distance (the distance the vehicle travels while the brakes are applied).
The stopping distance of a vehicle can be calculated using the following formula:
Stopping distance = reaction time + distance traveled during reaction time + braking distance
In this formula, the reaction time is the time it takes for the driver to recognize the hazardous situation and initiate a response, the distance traveled during reaction time is the distance the vehicle travels during this time period, and the braking distance is the distance the vehicle travels while the brakes are applied.
It is important for drivers to be aware of their reaction time and how it can affect their stopping distance. Factors that can affect reaction time include a driver's level of alertness, the complexity of the driving situation, and the driver's age, among others. By understanding their reaction time and the factors that can affect it, drivers can better anticipate and respond to hazardous situations on the road, helping to reduce the risk of accidents and injuries.
On a planet whose radius is 1.2×1010m, the acceleration due to gravity at the surface of the planet is 15m/s2. What is the mass of the planet?plese help me
Refer to the photo taken.
Twin sisters Paola and Maria have a slight difference in their handwriting. Paola slants her letters more than Maria does. Which of the following elements BEST describes the area in which their handwriting differs?
A.
mechanical
B.
physical
C.
style
D.
emotional
Answer:
C. Style
Explanation:
Because if your letters are slanted, it's not mechanical, is it? Neither is it emotional, since that's just not right. As for physical, how is your letters being slanted physical? Therefore, the best answer would be C. Style.
Brainliest, Please!a 2kg ball rolls at a speed of 4m/s. if friction slows it down to 3m/s, how much work did it do?
The work done by friction in slowing down the ball from 4 m/s to 3 m/s is 7 J.
What is workdone?Work is said to be done whenever a body is moved by a force through a certain distance.
To calculate the work done by friction, in slowing down the ball, we use the formula below.
Formula:
W = m(u²-v²)/2........ Equation 1Where:
W = Work done by friction in slowing down the ballm = Mass of the ballv = Final speed of the ballu = Initial speed of the ballFrom the question,
Given:
m = 2 kgu = 4 m/sv = 3 m/sSubstitute these values into equation 1
W = 2(4²-3²)/2W = 2×7/2W = 7JHence, the work done by friction is 7 J.
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Compare the magnitude of the electromagnetic and gravitational force between two electrons separated by a distance of 2.00 m. Assume the electrons have a mass of 9.11 × 10–31 kg and a charge of 1.61 × 10–19 C. Round to two decimal places. Fe = × 10–29 N Fg = × 10–71 N F Subscript e baseline over F Subscript g baseline.= × 1042
Two metal spheres with the same charge, q, are in contact and experience an electrostatic force of magnitude F. 2.3x10 N 66.
What connection can be seen between the mass of the items, their distance from one another, and the strength of the gravitational pull between them?A mass-bearing item will pull toward another mass-bearing object. The strength of the force is directly proportional to the masses of the two objects and inversely proportional to the square of their distances from one another.
How much do two electrons separated in space weigh in terms of electrostatic and gravitational forces?Consequently, the ratio of electric to gravitational force between two electrons is 4.17 1042.
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how far does a single point on a string move during one period of a transverse wave that passes by that point?
Distance between two waves' crests or troughs , λ = v/k
What is distance?
Distance is the sum of an object's movements, regardless of direction. Regardless of an object's beginning or finishing position, distance may be defined as the amount of ground it has traversed.
The speed at which a wave moves with particles oscillating about their mean location is known as its way velocity.
v = kλ is the formula for calculating wave velocity.
Where f represents the wave frequency or the number of waves passing through a place in a given amount of time.
The distance between two waves' crests or troughs that follow one another = λ
therefore distance, λ = v/ki
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if a simple pendulum oscillates with small amplitude and its length is doubled, what happens to the frequency of its motion?
When the length of a simple pendulum, which oscillates with minimal amplitude, is doubled, the frequency of the oscillation stays the same.
What is the meaning of amplitude?
In physics, amplitude refers to the greatest displacement or distance that a spot on a vibration or wave can move relative to its equilibrium location. It is equal to the half-length of the vibration path.
What is the amplitude measured in?
The amplitude, which is measured in metric units (m), is the largest displacement that a medium's particles can experience from their average positions during the propagation of a wave. Meters are the SI unit of displacement. So, the amplitude unit in SI is the meter.
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The force of impact at 20 mph is what times that at 10 mph speeds
The force of impact at 20 mph is two times that at 10 mph speeds.
What is effect of force?An object can change its size or shape, begin moving, stop moving, accelerate, or decelerate as a result of a force acting on it. When two things contact, they exert pressures on one another that are identical in size but directed in the opposite direction.
The combined effect of all the forces acting on an object is known as the "resultant force," and it is the same as if only one force were to be operating on the object in that direction. To alter an object's velocity, the resulting force is necessary.
The force required for increasing speed 20 mph of an object of mass m at an interval of time t be = m×20/t.
The force required for increasing speed 10mph of an object of mass m at an interval of time t be = m×10/t.
Hence, the force of impact at 20 mph is two times that at 10 mph speeds.
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which of the five scientists discussed in chapter 21 constructed the heliocentric model of the solar system placing the sun at the center?
Nicolaus Copernicus constructed the heliocentric model of the solar system placing the sun at the center.
Heliocentric is the model we use today, where we all revolve around the sun. Geocentric was a model that was long ago discarded after the discovery of telescopes.
The heliocentric model opposes the geocentric model by placing the sun at the center of the solar system as opposed to the earth as it is with the geocentric model.
It is a model in which Nicolaus Copernicus believed that the sun was in the center of the solar system and other celestial bodies were revolving around this.
This was Nicolaus's unorthodox idea that he was having in his mind and constructed the model which was later supported by Galileo and was established by Galileo that this model was correct.
Therefore, Nicolaus Copernicus constructed the heliocentric model of the solar system placing the sun at the center.
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The block is pushed by an
outside force.
Is energy conserved or not?
Answer:yes
Explanation:
How much work is done by a 10 N frictional force which slows a moving block to a stop after a displace ment of 5.0m to the right?
a) 50J
b) -50J
c) 25J
d) -25J
Answer:
a)
Explanation:
work done = Fscosθ
=(10)(5)(cos0⁰)
=50J
A 3,565 kg car moving at 27.2 m/s hits a stationary truck with a mass of 3,692 kg. If the two vehicles become stuck together in the collision, how fast do they move away from the point of impact?
To solve this problem, we can use the principle of conservation of momentum, which states that the total momentum of a system remains constant unless acted on by an external force. In this case, the initial momentum of the car before the collision is 3,565 kg * 27.2 m/s = 97,068 kgm/s, and the initial momentum of the truck before the collision is 0 kgm/s, since it is stationary. After the collision, the two vehicles become stuck together and move away from the point of impact with a combined mass of 3,565 kg + 3,692 kg = 7,257 kg. Since the total momentum of the system must remain constant, the combined velocity of the two vehicles after the collision must be equal to the total initial momentum of the car and truck before the collision, or 97,068 kg*m/s.
Therefore, the combined velocity of the two vehicles after the collision is 97,068 kg*m/s / 7,257 kg = 13.4 m/s. This is the speed at which the two vehicles move away from the point of impact. Note that this is a bit less than half the initial speed of the car before the collision, which is expected since the combined mass of the car and truck is greater than the mass of the car alone, and the momentum of the system must be conserved.
A skydiver dives from an airplane. air resistance is measured each second following the skydiver’s jump.
Time after jump | Weight | Air Resistance
1 sec | 500 N | 200 N
2 sec | 500 N | 300 N
3 sec | 500 N | 400 N
4 sec | 500 N | 500 N
Which statement best identifies her speed at each second?
a. The skydriver has the slowest speed at 2 seconds
b. The skydriver has the fastest speed at 4 seconds
c. The skydriver has the slowest speed at 1 second
d. The skydriver has the fastest speed at # seconds
The statement that best identifies her speed at each second is as follows: the sky driver has the fastest speed at 4 seconds (option B).
What is air resistance?Air resistance is the action of friction that slows something moving through air.
Air resistance is dependent on velocity, area, and shape of the object going through the air. Altitude, temperature, and humidity change air density and, consequently, its resistance.
The higher the speed and the bigger the area, the higher the resistance. As speed increases so too does the frequency of the collision of air molecules with the object. This results in an increase in air resistance.
Therefore, as the sky driver with a weight of 500N increases in air resistance, the speed also increases.
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Please help! Will mark brainliest
Answer:
Runner B
Explanation:
its just displacement over change in time
for a constant force, suppose the duration of impact on an object is doubled. a. how much is the impulse increased? b. how much is the resulting change in momentum increased?
Momentum is force * time. Momentum is also a change of momentum. that's why,
power * time
=
change in dynamics
For constant force, doubling the collision time doubles the momentum, resulting in a doubling of the momentum change.
The change in momentum is equal to the product of the change in mass and velocity. The mass remains the same because it is a constant value. It is the change in velocity that causes the change in momentum. The change in momentum is denoted by the symbol Δp.
What is the formula for momentum change?
1) The change in momentum is equal to the product of the change in mass and velocity. ⇒ΔP=m.
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Answer:
Explanation:
Momentum is force * time. Momentum is also a change of momentum. that's why,
power * time
=
change in dynamics
based on what you know about asteroids, select all of the correct statements from the following list.
These are the correct statements. 1) Most asteroids show no evidence of geological activity. 2) Most asteroids have been broken by impacts. 3) There are some asteroids found in Jupiter's orbit. 4) Kirkwood's gaps are caused by Jupiter.
Asteroids have no internal heat, so they are not geologically active.
The asteroids were formed in the early solar system from the gradual agglomeration of smaller particles. Their growth was restricted because of mutual collisions that impacted them to fragment.
The Jupiter trojans are found in the planet Jupiter's orbit.
The Kirkwood gaps are created by the orbital resonances between Jupiter and the asteroid belt. Orbital resonances is defined as the simple integer ratios of the distances between bodies in the case the overlapping gravitational forces create a pattern of strong and weak gravitational fields.
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At which reference point should your vehicle appear to intersect with the curb when parallel parking?
The reference point at which vehicle appear to intersect the curb is 2.22km.
To ensure that every parallel park is successfully completed, it is crucial to employ a structured technique and to practice it until a level of proficiency is attained. However, contrary to popular belief, it need not be completed in a single seamless maneuver.
During the maneuver, it is acceptable to advance and make adjustments as long as you do so safely and keep an eye on your surroundings at all times.
Utilizing reference points, a structured technique is applied. Whatever method is used to parallel park, using reference points will help new drivers complete this maneuver.
You should slightly pass the car you plan to park behind. The front of this car is aligned with the center of your passenger-side front window in reference point.
[tex]Reference=\frac{\pi }{\sqrt{2} }[/tex]
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what is the maximum horizontal force that can be applied to the lower block without the upper block slipping?
The maximum horizontal force that can be applied to the lower block without the upper block slipping is 4.7 N.
We know that, F net = m * a
Given that, mass of the first block = 0.5 kg
Mass of the lower block = 1 kg
The coefficient of friction between the bigger block and the table is 0.2.
The two blocks have 0.35 coefficient of friction.
The force between the table and the blocks is
F k = 1.5 * 9.8 * 0.20 = 2.94 N
The force between the two blocks is
F s = 0.5 * 9.8 * 0.35 = 1.1715 N
So, the maximum horizontal force is
1.715 = Fa - 2.94
Fa = 1.715 + 2.94 = 4.655 N = 4.7 N
Thus, the maximum horizontal force that can be applied to the lower block without the upper block slipping is 4.7 N.
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Maryam used the graduated cylinder to measure the volume of an unknown liquid in the physics lab the volume she measured was 46.0 mL then the teacher asked her to mix it with 1.20 mL of water (what is the value of the mixture in (L) )
The total volume of the liquid in the graduated cylinder in liters is 0.0472 L.
What is the total volume of the mixture?The total volume of the mixture is the sum of the volume of all the liquid in the cylinder.
Mathematically, the formula for the total volume of the liquid in the graduated cylinder is calculated as follows;
V ( total ) = volume of the liquid + volume of the water
The given parameters include the following;
The volume of the liquid in the graduated cylinder = 46 mL
The volume of water in the graduated cylinder = 1.2 mL
The total volume of the liquid in the graduated cylinder is calculated as;
V (total) = 46 mL + 1.2 mL
V (total) = 47.2 mL
The total volume of the liquid in the graduated cylinder in liters is calculated as;
V (total in liters) = 47.2 mL / 1000 = 0.0472 L
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the length of the path traveled by light in a vacuum in 1/299,792,458th of a second
A vacuum is an area devoid of matter, also referred to as "free-space." Practically speaking, only partial vacuums are feasible.
What do you meant by vacuums?North Americans typically refer to this electrical device as a vacuum cleaner or just a vacuum, whereas Britons typically refer to it as a hoover.
Both terms can be inflected to become verbs such as vacuumed, vacuuming, hoovered, and hoovering. A vacuum is an area devoid of matter, also referred to as "free-space."
Practically speaking, only partial vacuums are feasible. A great bagless upright vacuum, a respectable cordless vacuum, and a simple (but effective!) robot vacuum are just a few of the several vacuums we suggest; they typically cost around $150. Since the middle of the 19th century, a British person has been referred to as a "Limey" (from lime or lemon) in slang.
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how much heat, in joules, does it take to raise the temperature of 225.0 g of water from 25.0°c to 100.0°c ?
The heat required to raise the temperature of 225.0 g of water from 25.0°c to 100.0°c is 70,537.5J
Heat = specific heat capacity of the substance × mass of the substance in grams × temperature difference
Let us rewrite the equation as
q=mcΔT
Where q is the heat required, m is the mass of the substance, c is the specific heat capacity of the substance and ΔT is the temperature difference.
m=225g
ΔT=100-25=72
c=4.18J/gC
Let us substitute the values.
q=225×75×4.18
q=70537.5J
What is specific heat capacity?
Specific heat capacity, or simply specific heat, refers to the heat capacity per unit mass of a pure substance. In other words, it is defined as the amount of heat needed to increase the temperature of 1kg of a material by 1K and is expressed in terms of J/kg·K or equivalently J/kg·°C.
How do you calculate the specific heat of water?
The specific heat capacity of water is 4.18 J/g/°C. We wish to determine the value of Q - the quantity of heat. To do so, we would use the equation Q = m•C•ΔT. The m and the C are known; the ΔT can be determined from the initial and final temperature.
Thus, the heat required is 70537.5J
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A dart with a mass of 0.6 kg is thrown at 10.8 m/s and sticks into a 1.9 kg apple hanging
on a string. What is the velocity of the dart and apple just after the dart is embedded?
Hello,
I hope you and your family are doing well!
To find the velocity of the dart and apple just after the dart is embedded, we can use the principle of conservation of momentum. According to this principle, the total momentum of a closed system (such as the dart and apple) is constant, meaning that the total momentum before and after an interaction (such as the dart being thrown) must be the same.
The momentum of an object is equal to its mass times its velocity, so the total momentum of the dart and apple before the dart is thrown is:
p1 = (0.6 kg)(10.8 m/s) + (1.9 kg)(0 m/s) = 6.48 kg*m/s
After the dart is thrown, the total momentum of the dart and apple is:
p2 = (0.6 kg)(v) + (1.9 kg)(v) = 2.5v kg*m/s
Since the total momentum before and after the interaction must be the same, we can set p1 equal to p2 and solve for v:
6.48 kgm/s = 2.5v kgm/s
v = 6.48 kgm/s / 2.5 kgm/s
v = 2.592 m/s
The answer is 2.592 m/s.
Please consider leaving 5 stars and brainliest if you find this answer helpful.
Happy Holidays!
Answer: To find the velocity of the dart and apple after the dart is embedded, you can use the principle of conservation of momentum. This principle states that the total momentum of an isolated system remains constant, unless acted upon by an external force.
In this case, the dart and apple form an isolated system, so their total momentum must remain constant.
The momentum of the dart before it is embedded is given by the formula p = mv, where p is momentum, m is mass, and v is velocity. The momentum of the dart is therefore 0.6 kg * 10.8 m/s = 6.48 kg*m/s.
After the dart is embedded, the total momentum of the dart and apple is also 6.48 kg*m/s. We can find the velocity of the combined system using the same formula, p = mv. The mass of the combined system is the sum of the masses of the dart and apple, or 1.9 kg + 0.6 kg = 2.5 kg.
Substituting these values into the formula, we get:
p = mv
6.48 kg*m/s = 2.5 kg * v
v = 2.592 m/s
This is the velocity of the dart and apple after the dart is embedded.
what is the final speed of the stationary ball if the incoming ball is much more massive than the stationary ball?
Similar to a head-on shot only with cue ball on a pool table, the projectile shall come to rest and the target will go off with an equal velocity for a head-on impact with a stationary vehicle of equal mass.
Is final velocity and speed same?It's easy to understand why. Velocity is the pace and orientation of an object's movement, whereas speed is really the time rate that an object is travelling along a path. In other words, velocity is a vector, whereas speed is just a scalar value.
How can a distance-time graph be used to determine final speed?The gradient of a line - of - sight graph is equal to the alteration in space divided by the difference in time. Thus, the grade of a graph of distance vs time is equal to the speed of a item whose motion is captured by the line that plots the changes in distance over time.
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Draw a circuit diagram to show how water conducts electricity
Given is the diagram to show that water conducts electricity.
Water is a good conductor of electricity. The ions in the water conduct electricity because of their positive and negative charges. When the electrolytes tend to dissolve in the water, they get split into cation or positively charged and anions or negatively charged particles.
Take a beaker and fill it half with water.Connect a battery with a bulb and switch along with two rods as shown in figure.Put the rods in beaker.Turn on the switch.The bulb glows.Now remove water from beaker and then repeat the steps.
You will observe that bulb doesn't glow.
This experiment confirms that water is good conductor of electricity.
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Sport question:
Move used in many sports where the ball carrier keeps one foot planted on the ground but is allowed to rotate on that foot
Answer:
That move is called a pivot foot.
Explanation:
a 6 kg box is pushed with a force of 41 n at the moment it starts to accelerate from rest across the carpet. calculate the coefficient of static friction between the box and the carpet.
The coefficient of static friction between the carpet and the box is found to be 0.68.
The mass of the box is 6 kg and a force f of 41 newton is applied at the moment it starts to accelerate from rest across the carpet. If the net force is f and the force of friction between the carpet and the box is Fr.
We can write,
f = Fr
We know, force of friction is given by,
Fr = uN
N is the normal that is equal to weight of body,
u is the coefficient of static friction between the carpet and the box.
Putting values,
f = uN
41 = u(6×10)
u = 41/60
u = 0.68
So, the coefficient of static friction is found to be 0.68.
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what wavelength of light has a frequency of 1.8 x 1013 s-1? what is the energy of one photon of that light?
The energy of one photon of the light is 1.19 x [tex]10^{-11}[/tex] J.
What is Planck's equation?
According to this, electromagnetic radiation from heated bodies emits in discrete energy units or quanta, the size of which depends on a fundamental physical constant (Planck's constant).
We know that,
E = hν
Where,
E = Energy
h = Planck's constant
ν = Frequency
Note: Planck's constant has value of 6.63 × [tex]10^{-3}[/tex][tex]\frac{J}{s}[/tex]
Putting values in the given formula
E = 6.63 × [tex]10^{-3}[/tex] [tex]\frac{J}{s}[/tex] × 1.8 × [tex]10^{13}[/tex] [tex]s^{-1}[/tex]
E = 1.19 x [tex]10^{-11}[/tex] J.
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A thermodynamic process occurs in which a system changes by -8 J/K. According to the second law of thermodynamics, what can you conclude about the entropy change of the environment? (a) it must be -8J/K or less (b) it must be equal to -8 J/K (c) it must be between -8J/K and zero (d) it must be zero (e) it must be between zero and +8J/K (f) it must be equal to +8J/K (g) it must be +8 J/K or more (h) we need to know the nature of the process to reach a conclusion (i) it is impossible for the system to have a negative entropy change.
The entropy change of the environment is an increase in entropy. So, it must be +8 J/k or more.
The second law of thermodynamics says that any spontaneously occurring process always affects escalation in the entropy (S) of the universe. In simple words, according to this law, an isolated system's entropy never decreases over time.
The law itself mentions that the entropy of an isolated system can't decrease. This is because isolated systems spontaneously evolve towards thermodynamic equilibrium. So, the entropy of the environment will increase.
In some cases the system may be in thermodynamic equilibrium or may go through a reversible process, then the total entropy of a system and its surroundings will remains constant.
The correct answer is option (g) it must be +8J/k or more.
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The block slides down an inclined track to a infinite length flat surface. The block comes to a stop on its own. Is energy being conserved or not conserved?
Energy is conserved as the block slides down because kinetic energy is converted to heat energy.
Is energy conserved?We are looking at the principle of the conservation of energy. We know that the principle of the conservation of energy states that energy can neither be created nor destroyed but it can be converted from one form to another.
Now we know that the energy of the block would remain constant. Given the fact that energy is not created or destroyed, we can see that as the block is sliding down, the block would be loosing energy thus it would become slower. This is because of the fact that friction is working against the movement of the block and the energy that is lost is converted to heat.
Thus we can say that the energy is converted to heat as the the block is slowing down thus energy is conserved.
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A 5.5 Kg rock falling in air experience a force due to air resistance of 50N. What is the acceleration
Answer:
F1 = ma = 5.5 kg * 10 m/s² = 55 N (force acts downwards)
F2 = - 50 N (force acts upwards)
net force = 5 N (downwards)
F = ma
a = F/m
a = 5 / 5.5
a = 0.91 m/s²
Explanation:
Since the object is falling downwards, the air resistance acts upwards. We also have a force acting downwards since the rock experiences gravitational acceleration (the value of g above is 10 m/s² for the sake of easier calculation but you can also set it to be 9.81 m/s² which is the more accurate value). Since the air resistance and force due to gravity are acting in opposite directions and force is a vector, we have to put a minus in front of F1 or F2 (it doesn't matter which direction you chose to be the positive one) . Then we calculate the net force, aka the difference between F1 and F2. Finally, knowing the force and the mass, we can calculate the acceleration.
Is the coefficient of friction between the sole of a shoe and a given surface the same as the coefficient of friction between the top of the same shoe (vamp of shoe) and the surface? Explain
With shoes without slip-resistant bottoms, the coefficient of friction on ice, wet, and oily surfaces can be as low as 0.1. On brushed concrete, rubber-soled shoes can produce a coefficient of friction greater than 1.0.
Does the coefficient of friction differ between different surfaces?The nature of both surfaces affects the coefficient of friction between two surfaces. For instance, a block of ice will have a different coefficient of friction on a surface made of copper than a block of wood will have on the same surface.
What is the amount of friction there is between the surface and the object?The friction coefficient is the ratio of the normal force pressing two surfaces together to the frictional force preventing motion between them. Typically, it is represented by the Greek letter mu (). In terms of math, is equal to F/N, where F stands for frictional force and N for normal force.
Is the friction coefficient constant?Motionless items frequently experience greater friction than moving ones, requiring more power to set them in motion than to keep them there. The coefficient of friction between moving and stationary objects is not always the same.
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