14 mΩ should the internal resistance be for the maximum current in
the above situation to be 1.00 mA or less .
What is internal resistance ?
Internal resistance refers to the resistance to current flow provided by the cells and the battery itself, resulting in heat generation. Internal resistance is measured in ohms. The relationship between the internal resistance (r) and electromotive force (e) of cell s is given by
e = I (r + R)
where e = EMF, or H. electromotive force (volts), I = current (A), R = load resistance, r is the internal resistance of the cell, measured in ohms.
Rearranging the above formula, we get: e = IR + Ir or e = V + Ir
In the above equation, V is the potential difference (clamp) across the cell when current (I) is flowing through the circuit.
r = E-Ir/I
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A rocket is launched straight up with a speed of 12 meters per second near the surface of Earth. [Neglect air friction.]
Answer:
Explanation:
H = V² / (2·g)
H = 12² / (2·9.8) ≈ 7,3 m
Answer:
By conservation of energy,
Kinetic energy of launched rocket = change in potential energy of rocket at maximum height.
→ Ig h is maximum height reached:
Which kind of wave is a wave on the electromagnetic spectrum?
O mechanical wave
O longitudinal wave
O transverse wave
O matter wave
Mechanical wave is a kind of wave is a wave on the electromagnetic spectrum.
What is electromagnetic spectrum?Electromagnetic (EM) waves are cross waves. Their vibrations or oscillations are swapped in electrical and magnetic fields at right angles to the direction of wave travel. The radiation is explained by the amount of energy found in the photons. Radio waves have photons with low energies, and microwave photons ..Electromagnetic waves with smaller wavelengths and higher frequencies include ultraviolet light, X-rays, and gamma rays. Electromagnetic waves with longer kinds of Electromagnetic Waves. Radio Waves have the longest wavelengths of all electromagnetic waves.
So we can conclude that the different types of waves are mechanical and electromagnetic waves. Mechanical waves are divided into transverse and longitudinal waves.
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As part of an experiment on Mythbusters, a car was dropped from a crane 131 m (approximately 430 ft) above the
ground. If you assume there is no air resistance,
(a) how long would it take for the car to reach the ground?
(b) with what velocity will the car hit the ground?
A. The time taken for the car to reach the ground is 5.17 s
B. The velocity with which the car will hit the ground is 50.666 m/s
A. How do I determine the time taken for the car to reach the ground?
We can simply obtain the time taken for the car to reach the ground as illustrated below:
Height (h) = 131 mAcceleration due to gravity (g) = 9.8 m/s²Time (t) = ?h = ½gt²
131 = ½ × 9.8 × t²
131 = 4.9 × t²
Divide both side by 4.9
t² = 131 / 4.9
Take the square root of both side
t = √(131/ 4.9)
t = 5.17 s
Thus, the time taken is 5.17 s
B. How do I determine the velocity with which the car will hit the ground?
The velocity with which the car will hit the ground can be obtained as follow:
Initial velocity (u) = 0 m/sTime (t) = 517 sAcceleration due to gravity (g) = 9.8 m/s²Final velocity (v) =?v = u + gt
v = 0 + (9.8 × 5.17)
v = 0 + 50.666
v = 50.666 m/s
Thus, the velocity is 50.666 m/s
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A lever and fulcrum are used to raise a heavy rock, which has a weight of 445 N. If the lever has a mechanical advantage of 9.50, what must the input force on the lever be in order to lift the rock?
The input force on the lever of mechanical advantage 9.5, in order for it to lift a rock of 445 N is 46.84 N.
What is force?Force can be defined as the product of mass and acceleration.
To calculate the input force on the lever, we use the formula below.
Formula:
E = W/M.A......... Equation 1Where:
E = Input forceW = Weight of the rockM.A = Mechanical advantage of the leverFrom the question,
Given:
W = 445 NM.A = 9.50Substitute these values into equation 1
E = 445/9.5E = 46.84 NHence, the input force on the lever is 46.84 N.
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I JUST NEED ANSWER Mass mA rests on a smooth horizontal surface, mB hangs vertically. a) If mA =15.0 kg and mB =3.0 kg in the figure (Figure 1), determine the magnitude of the acceleration of each block. b) If initially mA is at rest 1.200 m from the edge of the table, how long does it take to reach the edge of the table if the system is allowed to move freely? c) If mB =1.0 kg , how large must mA be if the acceleration of the system is to be kept at [tex]\frac{1}{100}[/tex] g?
a) the magnitude of the acceleration of the block is a = 1.633m/s².
b) time to reach the end by the block is t = 1.1867s.
c) mass of mA if the acceleration of the system is 1/100g is mA = 99kg
a) Given,
mA = 15kg
mB = 3kg
The formula for the Tension in the cord, T =mAmBg / (mA + mB)
T = 45*9.8/18
T =24.5N
In the case of mA, we have T = mA*a
acceleration of mA, a = T/mA
a = 24.5 / 15
a = 1.633m/s²
In the case of mB, we have mB*a = mB*g -T
a = (mB*g -T)/mB
a = (3*9.8 - 24.5) /3
a = 1.633m/s²
b) Initial velocity of mA, u = 0
The distance traveled by mA, s = 1.15m
We have,
s = ut + 1/2at²
t = √(2s/a)
t = 1.1867s
c) mB = 1kg
The acceleration of the system, a = g/100
The acceleration of the system is given by the formula, a = mB*g/ (mA + mB)
mA = [mB*g/a] - mB
mA = [1*9.8*100/9.8] -1
mA = 99kg
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On a sunny day with clear roads, Freddie is going 5 m/s over the speed limit with a deceleration of 2g and he runs a red light. What is his speed as he goes through the light?
Answer: The most widely accepted method of determining the posted speed limit is to set the speed limit at what is called the “85th percentile speed”, which is the speed at or below which 85 percent of the traffic is moving.
Explanation:
Which characteristic of Earth’s orbit are in agreement with Kepler’s second law
The features of Earth's orbit that concur with and conform to the pattern of Kepler's second law include the fact that Earth feels the largest gravitational pull when it is closest to the Sun.
In which of the following is Kepler's second law stated?According to Kepler's second rule, a planet moves in its ellipse so that a line drawn between it and the Sun and focused on it covers the same amount of space in the same amount of time.
What features distinguish the earth's orbit?The eccentricity of the Earth's orbit around the Sun, which is an ellipse, determines how far from a circle the orbit is (e). The perihelion, or point on the orbit that is closest to the Sun, and the apogee, or point most aphelion of the Sun.
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A large water tank is completely filled with water. The tank is 3.0 m high and its surface is open. If a small hole is made on one side of the tank at a height of 0.8 m, calculate the speed with which the water comes out of the pipe.
The speed of the water through the pipe is 4.96 m/s
How to calculate the speed at which the water comes out of the pipe?Since a large water tank is completely filled with water. The tank is 3.0 m high and its surface is open. If a small hole is made on one side of the tank at a height of 0.8 m, to find the speed with which the water comes out of the pipe, we use Bernoulli's equation
What is Bernoulli's equation?Bernoulli's equation governs flows through pipes. It is given by
P₁ + ρgh₁ + 1/2ρv₁² = P₂ + ρgh₂ + 1/2ρv₂² where
P₁ = pressure at point 1,h₁ = height at point 1,v₁ = speed at point 1,P₂ = pressure at point 2,h₂ = height at point 2, andv₂ = speed at point 2Given that
P₁ = atmospheric pressure = 1.013 × 10⁵ Pa,h₁ = height of tank = 3 m,v₁ = speed at top ot tank = 0 m/s (since it is stationary there),P₂ = pressure at bottom of tank = 0 Pa,h₂ = height at hole = 0.8 m, andv₂ = speed at hole = speed of water through pipe and ρ = density of water = 1000 kg/m³So, susbstituting the values of the variables into the equation, we have
P₁ + ρgh₁ + 1/2ρv₁² = P₂ + ρgh₂ + 1/2ρv₂²
1.013 × 10⁵ Pa + 1000 kg/m³ × 9.8 m/s² × 3 m + 1/2 × 1000 kg/m³ × (0 m/s)² = 0 + 1000 kg/m³ × 9.8 m/s² × 0.8 m + 1/2 × 1000 kg/m³ × v₂²
1.013 × 10⁵ Pa + 29400kg/ms² + 0 = 0 Pa + 7840kg/ms² + 5000v²
130700 Pa = 7840kg/ms² + (5000 kg/m³)v²
130700 Pa - 7840 Pa = (5000 kg/m³)v²
122860 Pa = (5000 kg/m³)v²
Making v subject of the formula, we have
v = √(122860 Pa/5000 kg/m³)
= √(130.7/5 Pam³/kg)
= √(24.572 Pam³/kg)
= 4.96 m/s
So, the speed of the water through the pipe is 4.96 m/s
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jkjkjkjkdd ds fs d fsd ds f ssfd ds a? A ??DS?D
Answer:
hjcyysjjJjxjcmxmmsxjvemmzxjdndmenbxhfnhcjdnuxjd
Select the correct answer. What happens when a negatively charged object A is brought near a neutral object B? A. Object B gets a negative charge. B. Object B gets a positive charge. C. Object B stays neutral but becomes polarized. D. Object A gets a positive charge. E. Object A loses all its charge.
What happens when a negatively charged object A is brought near a neutral object B is that: B. Object B gets a positive charge.
The law of electrostatic forces.According to the law of electrostatic forces, unlike charges attract each other while like charges repel one another.
This ultimately implies that, objects that are having the same charges (like charges) would repel one another, and this causes a transfer of electrons (charges) to any differently charged object which comes in contact with it, through a process known as conduction.
In this context, we can reasonably and logically deduce that the negative charge of object A would induce an opposite charge (positive) on object B when a negatively charged object A is brought near a neutral object B.
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A cube of wood with a density of 0.780 g/cm' is 10.0 cm on each side. When the cube is placed in water, what buoyant force acts on the wood? (pw 1.00 g/cm')
The buoyant force acts on the cube of wood with a density of 0.780 g/[tex]cm^3[/tex] And 10.0 cm on each side is 7.644 Newton.
What is density?The density is the mass of a material substance per unit volume. d = M/V, where d is density, M is mass, and V is volume, is the formula for density. Grams per cubic centimeter are a typical unit of measurement for density.
As an illustration, the density of Earth is 5.51 grams per cubic centimeter, whereas the density of water is 1 gram per cubic centimeter.
Given:
The density of wood, ρ = 0.780 g/[tex]cm^3[/tex],
The Side of wood, a = 10 cm,
Calculate the buoyant force by the following formula,
F = - ρ * g * V,
Here, F is the buoyant force.
Substitute the values,
F = - 0.780 * 9.8 * [tex]10^3[/tex] * [tex]10^{-3}[/tex]
F = 7.644 Newton
Therefore, the buoyant force acts on the cube of wood with a density of 0.780 g/[tex]cm^3[/tex] is 10.0 cm on each side is 7.644 Newton.
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Suppose you are standing in the aisle of a bus that travels along a straight road at 100km/h and you have a pencil still above your head. Then relative to the bus the velocity of the pencil is 0km/h, and relative to the road the pencil had a horizontal velocity of
Answer: 100km/h
Explanation: This is because the road isn't moving. If you drew the roads velocity and the bus velocity you would find a 100km/h difference. Thus an object inside the bus would experience the same differential.
Which side of a cuboid should be placed on the ground to exert maximum pressure?
a) The smallest side
b) The largest side
c) The longest side
d) Each side will exert the same pressure on the ground
rocket launch checklist
Answer:
Checklist 1: What to Bring...Your Rocket Launch Pad & Ignition System Rocket MotorsIgnitersRecovery WaddingAltitude Tracker Your Field Box Also, it would be a good idea for the group to bring A folding card table or picnic table for rocket prep Trash Bags: try to leave your launch field cleaner than you found it. First Aid Kit: be prepared. A fly or tarp set up as a lean-to to protect the rocket prep area from the wind and/or sun.
PLEASE HELP DUE TODAY
Imagine you are an alien from a distant galaxy. Your home planet does not have any gravity. You have just landed on Earth and make a few observations about the planet.
1) What are some ways you might first observe gravity?
2) How might you test gravitational force?
3) How would you describe gravity to other aliens back at your home planet?
Use details to support your answer.
Answer:
1. some ways I might first observe gravity are... when I first arrive on earth I will see everything staying in one place on the ground and nothing will be floating
everywhere.
2. I might test gravitional force by jumping and seeing how fast I come down or by taking something and dropping it from above my head to the ground to see that it falls and doesn't float.
3.I woukd describe gravity to other aliens back at my home planet by #1 telling them that nothing floats, everything touches the ground and if u drop something from high above you will instantly/immediately fall back down to the ground.
You can say exactly this if you want bc I answered like how if u were gonna answer the question so your welcome
Answer:
1. some ways I might first observe gravity are... when I first arrive on earth I will see everything staying in one place on the ground and nothing will be floating
everywhere.
2. I might test gravitional force by jumping and seeing how fast I come down or by taking something and dropping it from above my head to the ground to see that it falls and doesn't float.
3.I woukd describe gravity to other aliens back at my home planet by #1 telling them that nothing floats, everything touches the ground and if u drop something from high above you will instantly/immediately fall back down to the ground.
Explanation:
if a car collides with a moving bus, what type of relationship exists between the force of the car and the force of the bus?
A: forces are not equal and in the opposite direction
B: forces are equal and in the same direction
C: forces are equal but opposite in direction
D: forces are not equal but in the same direction
Answer:
C: forces are equal but opposite in direction
Explanation:
If both objects are moving you know this is an elastic collision and therefore the bus and car will travel in opposite directions after the collision with equivalent forces.
if a car collides with a moving bus, the type of relationship exists between the force of the car and the force of the bus is the forces are equal but opposite in direction.
What are the types of force ?Force can be defined as pushing or pulling of any object resulting from the object’s interaction or movement, without force the objects can not be moved, can be stopped or change the direction.
Force is a quantitative interaction between two physical bodies, means an object and its environment, there are different types of forces in nature.
If an object in its moving state will be either static or motion, the position of the object will only be changed if it is pushed or pulled and The external push or pull upon the object called as Force.
The contact force types are the force that occurs when we apply some effort on an object such as Spring Force, Applied Force, Air Resistance Force, Normal Force, Tension Force, Frictional Force
Non-Contact forces are another type of forces occur from a distance such as Electromagnetic Force, Gravitational Force, Nuclear Force
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Whitch is true of high resistsncce wires
The longer a wire is, the higher the resistance will be.
Neither length (L) nor cross-sectional area (A) influences Rh. It totally depends on the type of material used to make the wire. It is somewhat dependent on temperature variation, but this variation is negligible and is disregarded for most purposes.
Let Resistivity be Rh and Resistance be R.
L for the wire's length and A for its cross-section.
This formula relates to resistance.
R=Rh*L/A
Rh, L, and A are the three parameters that determine resistance.
The resistance increases as the wire lengthen.
Less resistance is there the larger the cross-sectional area. (Put A in the denominator; the numerator is L.)
Only take into account the Length variable. As was previously said, shorter wires have lower resistance and vice versa.
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Give causes, Prevention and cure of diseases of Respiratory System.
any volunteer?
In respiratory system, Airflow from the lungs becomes obstructed due to chronic inflammatory lung disease called chronic obstructive pulmonary disease (COPD).
Respiratory system :
The network of organs and tissues that aids in breathing is known as the respiratory system.
The most common respiratory diseases are :
asthmachronic obstructive pulmonary diseasecystic fibrosislung cancertuberculosisbronchitisProblem causes respiratory system are :
tobacco smoking air pollution allergensoccupational risksPrecautions of respiratory system diseases :
Do not smoke. Improve the indoor air quality .Exercise. Do breathing exercises.regular hand washing.Do not exchange personal items.In respiratory system, Airflow from the lungs becomes obstructed due to chronic inflammatory lung disease called chronic obstructive pulmonary disease (COPD).
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staff members at the mental health center do not respond to patients who use threats, but praise patients who are polite. Which of the following psychotherapeutic approaches is being used? A. Behavioral therapy B. Cognitive therapy C. Humanistic therapy D. Psychoanalytic therapy E. Assertiveness training
In this case Behavioral therapy is being used.
What is Behavioral Therapy?
A broad phrase used to describe several forms of therapy used to address mental health conditions is behavioural therapy.
This type of treatment aims to recognize and assist in changing potentially harmful or unhealthy behaviors. It is predicated on the notion that all behaviors are taught and that they are modifiable. Treatment frequently focuses on current issues and solutions.
When staff members at the mental health center do not respond to patients who use threats, but praise patients who are polite, they try to teach politeness and other good behavior by using Behavioral therapy.
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a vector of magnitude 20 is added to a vector of magnitude 25 the magnitude of this sum might be?
Answer:
It could be 45 if the vectors are parallel.
It could be 5 if the vectors are antiparallel.
It could be between 5 and 45 for any other arrangement of these two vectors.
Suppose they are at right angles to another then the sum is
(20^2 + 25^2)^1/2 = 32
When elections are shared, molecules are produced and ? Is formed
A. A natural bond
B. An iconic compound
C. A covalent compound
D. A hydrogen bond
elections are shared, molecules are produced, the correct answer is option
C. A covalent compound
What is covalent compound?
Covalent compounds are composed of atoms that are linked via covalent bonds i.e. bonds formed by mutual sharing of electrons. This is in complete contrast to ionic compounds which are held together by ionic bonds, i.e. bonds formed by complete transfer of electrons from one atom to the other.
In the given examples we have:
Barium nitrate: Ba(NO3)2 - Ionic
Dinitrogen tetroxide: N2O4- Covalent
Strong intramolecular linkages characterise covalent substances. This is due to the atoms within covalent molecules being very securely bound together. Each molecule is certainly distinct, and the attraction between individual molecules in a covalent complex is typically modest.
To split the molecules, we simply require a minimal amount of energy. This is owing to the molecules' attraction forces as well as a lack of total electric charge. Covalent compounds are typically gaseous molecules at ambient temperature and pressure. They could be liquids with extremely low boiling points.
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I know this isn’t the right subject but i need help
Expository with an a anecdote and explain how specific life even impact the character of an individual
The current state of research offers some evidence that life events can cause changes in personality traits and that various life events may connect differently to various trait domains.
What is anecdote?
A brief narrative or account abou life events changet a person or event that is typically humorous, instructive, entertaining, or biographical in nature is known as an anecdote.
How do life events change your personality?
These ideas contend that because life events alter, interrupt, or reroute people's habits of thought, feeling, and action, they have long-lasting consequences on personality traits.
Hence is a changes in personality traits a correct answer.
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2. A small china bowl having kinetic energy E is sliding
along a frictionless countertop when a server, with per-
fect timing, places a rice ball into the bowl as it passes
him. If the bowl and rice ball have the same mass, what
is the kinetic energy of the system thereafter? (a) 2E
(b) E (c) E/2 (d) E/4 (e) E/8
E/2 is the kinetic energy of the system thereafter.
[tex][KE_f=m2E/m/4],[=E/2][/tex]
The energy an item has as a result of motion is known as kinetic energy. An object's kinetic energy will remain constant as long as it is travelling at the same speed. The velocity and mass of an item are used to compute its kinetic energy. The kinetic energy may be significantly impacted by the square of the velocity, as seen in the equation.
The joule is the accepted measurement for kinetic energy (J). The joule serves as the universal unit of energy. While potential energy is caused by an object's location or condition, kinetic energy is caused by an object's motion. The velocity of an item plays a significant role in determining its kinetic energy.
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Express the Vector A=5ON at South east east in Polar form
Answer:
Explanation:
Polar form:
ρ = A = 50
φ = - 45°; φ = - π / 4
r = ρ·cos φ
r = 50·cos (- π / 4)
two solid spheres of radius R made os same steel is placed in contact and exerts a force of f1. if the radius is 3R, what will be the magnitude of gravitational force
The magnitude of the gravitational force 0f two solid sphere of radius R is 81F₁ newton.
Gravitational force :
Any two bodies' mutual attraction is directly proportional to the sum of their masses and inversely proportional to the square of their separation.
Force is given as :
F₁ = (G x m x m )/ (2r)²
To calculate gravitational force :
F₂ = G x [27m x 27m]/ [6r]²
F₂ = (G x27)² m² / 36r²
F₂ = (81 G x m²) / 4r²
F₂ = 81F₁
The magnitude of the gravitational force of two solid sphere of radius R is 81F₁ newton.
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A lorry pulls forward after initially being stationary, it takes the lorry 40m to reach a speed of 8m/s, calculate the lorry’s acceleration.
Answer:
0.8m/s²
Explanation:
we know,
v² = u² + 2as
here v is final velocity, u is initial velocity, a is acceleration & s is distance travelled.
8² = 0² + 2*a*40
⇒ 64 = 80a
⇒a = 64/80 = 0.8m/s²
If a 62 kg panther sits in a tree 1.3 meters above the ground, how much gravitational potential energy does it have?
If the air resistance cause the panther to lose 200 J of energy as it falls, what is the KE of the panther just before it hits the ground?
What was the velocity of the panther just before it hit the ground?
Gravitational Potential Energy , Kinetic Energy and velocity of panther just before hitting the ground will be 790.41599 J , 990.41599 J , 5.6523m/s respectively.
Mass is 62 kg with a height 1.3m .
Gravitational Potential Energy means product of mass , gravitational acceleration and height . Mathematically, GPE= mgh
GPE= 62 x 1.3 x 9.8
= 790.41599 J
Energy lost = Final energy- GPE
Final Energy Δ = 790.41599 J + 200 J
=990.41599 J
To find Velocity of panther just before hitting the ground V:-
Δ⇒mV²/2
990.41599 J= 62 V²/2
V²= {990.41599 x 2}/62
= 31.9489029
V=5.6523m/s
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When a constant force acts upon an object, the acceleration of the object varies inversely with its mass. When a certain constant force acts upon an
object with mass 5 kg, the acceleration of the object is 15 m/s². If the same force acts upon another object whose mass is 3 kg
what is this object's
acceleration?
25 m/s² is the object's acceleration
m1a1=m2a2
m1=5kg
m2=3 kg
a1= 15 m/s²
a2=?
m1a1=m2a2
a2=m1a1/m2
a2=5×15÷3
a2= 25 m/s²
Acceleration is a vector variable that describes the rate at which an object changes its velocity.
An object is said to be accelerating if its velocity is changing. Occasionally, a moving object can change its velocity by the same amount each second. a moving object whose speed fluctuates by 10 m/s every second. This is referred to as a constant acceleration since the velocity is changing by a fixed amount each second.
The difference between an object with a constant acceleration and one with a constant velocity must be understood. Do not be fooled! If an object's velocity changes, whether it does so by a constant amount or a variable amount, then it is accelerating. Furthermore, something that is travelling at a steady speed is not accelerating.
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A planet has a radius of 5 000 km. The acceleration of free fall of the planet is 6.05 m s-2. Determine the (i) Mass of the planet
(II) Escape velocity of the planet
Answer:
Explanation:
Given:
R = 5 000 km = 5*10⁶ m
g = 6.05 m/s²
G = 6.67·10⁻¹¹ m³/(kg*c²)
______________
M - ?
V - ?
(i)
g = G·M /R²
M = g·R² / G = 6.05·(5·10⁶)² / 6.67·10⁻¹¹ ≈ 2.27·10²⁴ kg·
(ii)
V = √ (g·R) = √ (6.05·5*10⁶) ≈ 5 500 m/s = 5.5 km/s
Did Donald Trump influence public policy?