Question 3
When a police officer is trying to decide if a driver is speeding, what is his point of reference?
The ground
His car
The speed limit
All of these
3) A bird flies toward a tree limb at a 45-degree angle to the ground along a path that is 50 m long landing on the limb. Determine, in m, how high above the ground the bird is perched.
Answer:
35 m
Explanation:
Given :
The distance of the path from the ground to the tree limb = 50 m
The angle between the path of flight of the bird towards the tree limb and the ground = 45 degrees
Therefore we can determine the height above which the bird perched above the ground by using the rules of the trigonometric ratios as;
We know that ,
[tex]$\sin 45^\circ =\frac{\text{perpendicular}}{\text{hypothenus}}$[/tex]
[tex]$\sin 45^\circ =\frac{\text{BC}}{\text{AC}}$[/tex]
[tex]$0.7 =\frac{\text{BC}}{\text{50}}$[/tex]
[tex]\text{BC }= 0.7 \times 50[/tex]
= 35
Therefore, the bird perched on the tree limb at a height of 35 m.
A force of 30.0 N is applied to a 3.00 kg object for 3.00 seconds. Calculate the velocity experienced by the object.
Answer:
Explanation:
F = ma and
[tex]a=\frac{v}{t}[/tex]
We have F, we have m, but in order to solve for v, we need a.
30.0 = 3.00a so
a = 10.0 m/s/s. Plug that in for a in the second equation and solve for v:
[tex]10.0=\frac{v}{3.00}[/tex] so
v = 10.0(3.00) so
v = 30.0 m/s
A small hole is made at the bottom of a plastic cup. If it is filled with water and allowed to fall freely, will waterfall down from the hole?
Answer:
It depends on how big the hole is.
Explanation:
If the hole is too big, the water will fall freely out of the cup. However, if it is just a small opening (from a needle, pencil/pen tip, etc.) the water pressure will be able to hold in the water.
In April 1974, Steve Prefontaine completed a 10.0 km race in a time of 27 min , 43.6 s . Suppose "Pre" was at the 7.71 km mark at a time of 25.0 min . If he accelerated for 60 s and then maintained his increased speed for the remainder of the race, calculate his acceleration over the 60 s interval. Assume his instantaneous speed at the 7.71 km mark was the same as his overall average speed up to that time.
Answer:
0.18 m/s²
Explanation:
The total time taken to cover a 10 km race is 27 min, 43.6 seconds.
At 25 min, Pre was at 7.71 km mark. Therefore the average speed = 7.71 km / 25 min = 7710 m / (25 * 60) s = 5.14 m/s
The distance remaining = 10 km - 7.71 km = 2.29 km = 2290 m
The remaining time = 27 min, 43.6 seconds - 25 min = 2 min 43.6 second = 163.6 seconds
She accelerates for 60 seconds, therefore the distance covered (S) during the acceleration (a) is:
S₁ = 5.14(60) + 0.5a(60)² = 308.4 + 1800a
She maintains the speed for the remaining distance (S₂). The remaining time = 163.6 seconds - 60 seconds = 103.6 seconds. The final speed after the acceleration = (5.14 + 60a) m/s
S₂ = (5.14 + 60a)* 103.6 = 532.5 + 6216a
S₁ + S₂ = 2290 m
(308.4 + 1800a) + (532.5 + 6216a) = 2290
8016a + 840.9 = 2290
8016a = 1449.1
a = 0.18 m/s²
How do you complete this mixed circuit?
For the resistor closest to the battery, drawn vertical in the diagram, I = 8 A and P = 320 watts.
Also, the battery voltage is 40 V.
There isn't enough information included in the picture to fill in any of the missing items for the other two resistors.
Đặt vào đầu hai dây dẫn cùng một hiệu điện thế bằng nhau U,có điện trở lần lượt là R1 và R2.Ta thấy cường độ dòng điện qua dây dẫn thứ nhất I1 lớn gấp hai lần cường độ dòng điện qua dây dẫn thứ hai I2
Answer:
The resistance ratio of first conductor to the second conductor is 1 : 2.
Explanation:
Current in first conductor = I1
Current in second conductor = I2 , I1 = 2 I2
According to the Ohm's law
[tex]V= I_1R_1..... (1)\\V = I_2 R_2 .... (2)\\[/tex]
From (1) and (2)
[tex]I_1 R_1 = I_2 R_2\\\\2I_2 R_1 = I_2 R_2\\\\2 R_1 = R_2[/tex]
the use of thermostat in a gas cooker is to
Explanation:
An oven thermostat regulates the temperature inside an oven. The thermostat's temperature-sensitive probe measures the oven's warmth, switching the heat on and off as necessary to maintain the correct temperature.
A block slides down a smooth inclined surface and the gap between the block and the surface contains viscous fluid. Assume the velocity distribution in the gap is linear, and the area of the block in contact with the vicious fluid remains constant. If you increase the inclined angle, the terminal velocity will Group of answer choices
Answer:
The velocity increases as the inclination increases.
Explanation:
hen a block moves downwards along the inclined plane, the viscous property of the fluid between the block and the inclined acts and thus there is a friction between the block and surface.
When gravitational force acting along the plane provides the acceleration of the block.
When the angle of inclination increases, the acceleration along the plane increases and thus the velocity increases.
Felipe drives his car at a velocity of 28 m/s. He applies the brake, which slows the vehicle down at a rate of 6.4 m/s2 and causes it to slow to a stop. How long does it take for the car to stop? Round your answer to the nearest tenth.
Answer:
4.4 seconds
Explanation:
use the equation
v(final)=v(initial)+a(t)
what we know:
v(initial)=28mps
v(final)=0 because it comes to a stop
a= -6.4 it is negative because the 6.4 is resisting forward motion
using these you get
0= 28 + (-6.4)t
6.4(t)=28
t=4.375 sec
and with rounding
t=4.4 sec
Answer:
4.4
Explanation:
i got it correct
PLEASE HELP WITH THIS QUESTION
What is one benefit of a seatbelt?
A. It decreases the passenger's inertia. B. It allows you to share the same motion as the vehicle
C. It makes you fly out of the car when stopping.
D. It prevents gravity from affecting the passenger
Answer:
D
Explanation:
why is so you don't go flying out of the car
a bell rings at a frequency of 75hz on a warm 25 degree evening. calculate the...
a. speed of the sound wave at this temperature.
b. wavelength of the sound wave
Answer:
Explanation:
We need 2 different equations for this problem: first the velocity of sound equation, then the frequency of the sound equation.
The velocity of sound is found in:
v = 331.5 + .606T
We need to find that first in order to fill it into the frequency equation which is
[tex]f=\frac{v}{\lambda}[/tex] where v is the velocity we will find the part a, f is frequency and lambda is the wavelength. Starting with the velocity of the sound:
v = 331.5 + .606(25) and
v = 331.5 + 15 and rounding correctly using the rules for sig fig when adding:
v = 347 m/s
Filling that into the frequency equation:
[tex]75=\frac{347}{\lambda}[/tex] and
[tex]\lambda=\frac{347}{75}[/tex] so
[tex]\lambda=4.6m[/tex]
what are scalar quantities and list their examples
Explanation:
these are quantities that have magnitude but no direction
Examples include : speed, mass, volume, density, everything, time
You plan to use a slingshot to launch a ball that has a mass of 0.019 kg. You want the ball to accelerate straight toward your target at 23 m/s2. How much force do you need to apply to the ball?
Answer:
Explanation:
this is a simple application of Newton's 2nd Law: F = ma.
F = .019(23) so
F = .44 N
You would need to apply a force of 0.437 Newtons to the ball in order to achieve the desired acceleration of 23 m/s².
Force is a physical quantity that describes the interaction between objects or systems and their ability to change motion or shape. It is a vector quantity, meaning it has both magnitude and direction. Force can cause an object to accelerate, decelerate, or change direction.
According to Newton's second law of motion, force is directly proportional to the mass of an object and the acceleration it experiences. The equation F = m × a represents this relationship, where F is the force, m is the mass of the object, and a is the acceleration.
Force can be measured in various units, such as Newtons (N) in the International System of Units (SI) or pounds (lb) in the US customary system. Common examples of forces include gravity, friction, tension, compression, and applied forces like pushing or pulling an object.
According to Newton's second law of motion, which states that force (F) is equal to mass (m) multiplied by acceleration (a):
F = m × a
In this case, the mass of the ball is given as 0.019 kg, and the desired acceleration is 23 m/s². Plugging these values into the equation, we can calculate the force:
F = 0.019 kg × 23 m/s²
F = 0.437 kg m/s²
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what is energy?what its si unit
Answer:
energy is the capacity or ability to do work
its si unit is joule
What is the amount of change in an object's momentum equal to?
A.
The amount of mass applied to the object over a certain amount of time
B.
The amount of force applied to the object over a certain amount of time
C.
The amount of acceleration applied to the object over a certain amount of time
D.
The amount of energy applied to the object over a certain amount of time
answer:
Explanation:
the impulse-momentum theorem states that the change in momentum of an object equals the impulse applied to it. The impulse-momentum theorem is logically equivalent to Newton's second law of motion (the force law).
According to the impulse-momentum theorem, the amount of change in an object's momentum equal to the amount of force applied to the object over a certain amount of time. So, option B.
According to the impulse-momentum theorem, the impulse that is applied to an item is equal to the change in momentum.
It shows how an object's change in momentum depends on both the strength and duration of the applied forces.
Impulse is defined as the force acting for a short interval of time.
Impulse = F x t
The momentum of the object,
P = mv
So, the rate of change of momentum,
dP/dt = d(mv)/dt
dP/dt = mdv/t
dP/dt = ma = Force
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A 2kg mass and a 4kg mass on a horizontal frictionless surface are connected by a massless string A. They are pulled horizontally across the surface by a second string B with a constant acceleration of 12 m/s^2. What is the magnitude of the force of string B on the 2kg mass?
Answer:
72 N
Explanation:
Applying,
F = (m'+m)a..................... Equation 1
Where F = Force, m' = First mass, m = second mass, a = acceleration.
From the question,
m' = 2 kg, m = 4 kg, a = 12 m/s²
Substitute these values into equation 1
F = 12(2+4)
F = 12×6
F = 72 N
If a 5.0Ω resistor, a 9.0Ω resistor, and a 13.0Ω resistor are connected in series with a 24.0 V battery, calculate the total resistance.
0.037Ω
0.89Ω
585Ω
27.0Ω
Answer: 27Ω
Explanation:
Quando o circuito está em série, a resistência total é igual ao somatório das resistências parciais do circuito.
A 1,000 kg car is travelling at 6.5 m/s to the North. A 3,500 kg truck is travelling South at the same velocity. What is the total momentum of the two vehicles (don’t forget to assign a NEGATIVE velocity to one of the vehicles, because they are travelling in opposite directions
please help asap
Answer:
Total momentum of both is 16250 kgm/s
Một dây dẫn mảnh được uốn thành một cung tròn bán kính 10cm, góc ở tâm bằng 1200, đặt trong không khí. Trong dây dẫn có dòng điện cường độ 30A chạy qua. Độ lớn của cảm ứng từ tại tâm của cung tròn là bao nhiêu ?
Answer:
Diana and that
Explanation:
muyayyano
Sandy wants to know whether an item dropped into a fluid will sink or float. What is true for any item that floats?
A.
The force of gravity is equal to the force of mass.
B.
The force of gravity is stronger than the buoyant force.
C.
The buoyant force is stronger than the force of gravity.
D.
The object has no density.
Answer:
A, I think but I'm sureExplanation:
ur welcomeee ♥️♥️
Answer: C.
The buoyant force is stronger than the force of gravity.
Explanation:because I did it
A skier of weight 700 N is pointed down a ski hill that has a slope angle of 25° above horizontal.
What is the component of his weight pulling him down the slope.
O 634N
O 326N
O 296N
O 700N
Answer:
O 296N
Explanation:
F_y = F*sin(x)
F_y = 700N*sin(25°)
F_y = 295.83N or 296N
PLease answer this question or explain
Which of the following stakeholders (who) expressed concern over the removal of the Bloede dam?
A Park Ranger
B Historian
C NOAA Scientist
Answer:
NOAA Scienctist
Explanation:
The stakeholder who expressed concern over the removal of the Bloede dam was the NOAA Scientist. So, option C.
What is meant by stakeholders ?A stakeholder is a person, group, or organization that has a vested interest in the choices made and the actions taken by a company, organization, or business initiative.
Here,
Stakeholders are important because, there wouldn't be any projects without them. The project can gain a lot from including its stakeholders.
They can participate in the decision-making process and have an impact on the organization's actions in a way that benefits the project management team.
The dismantling of Bloede Dam was long overdue given the environmental and safety concerns.
The difficulties caused by Bloede Dam are not unusual. Our nation's dams are increasingly hazardous to the environment and dangerous to people, with more than 90,000 dams blocking rivers around the country, including at least 659 in Maryland alone.
Hence,
The stakeholder who expressed concern over the removal of the Bloede dam was the NOAA Scientist. So, option C.
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A 75kg hockey player is skating across the ice at a speed of 6.0m/s. What is the magnitude of the average force required to stop the player in 0.65s?
Answer:
692.31 N
Explanation:
Applying,
F = ma............... Equation 1
Where F = Average force required to stop the player, m = mass of the player, a = acceleration of the player
But,
a = (v-u)/t............ Equation 2
Where v = final velocity, u = initial velocity, t = time.
Substitute equation 2 into equation 1
F = m(v-u)/t............ Equation 3
From the question,
Given: m = 75 kg, u = 6.0 m/s, v = 0 m/s (to stop), t = 0.65 s
Substitute these values into equation 3
F = 75(0-6)/0.65
F = -692.31 N
Hence the average force required to stop the player is 692.31 N
Bones are composed of three main components, what are they? (Choose all that apply)
Answer:
funny bone and compact bone
Explanation:
your funny bone only reacts if you hit it against something the compact bone is the heaviest and strongest bone in your body and the bone marrow is soft sponge like tissue in the center if most bones that produces white and red blood cells
A gymnast with mass 50kg suspends herself from lower end of a hanging rope, upper end of the rope is attached to the ceiling. What is the weight of gymnast? Which of the Newton’s law related to your calculation? if gymnast fall with an acceleration of 2m/s2 , what is the force on the rope?
Answer:
I. Weight = 490 Newton
II. Newton's Second Law of Motion
III. Force = 100 Newton
Explanation:
Given the following data;
Mass = 50 kg
Acceleration = 2 m/s²
I. To find the weight of the gymnast;
Weight = mass * acceleration due to gravity
We know that acceleration due to gravity is equal to 9.8 m/s².
Weight = 50 * 9.8
Weight = 490 Newton
II. Newton's Second Law of Motion states that the acceleration of a physical object is directly proportional to the net force acting on the physical object and inversely proportional to its mass.
Mathematically, it is given by the formula;
Force = mass * acceleration
[tex] F = ma[/tex]
III. To find the force, we would use the following formula;
[tex] F = ma [/tex]
[tex] F = 50 * 2[/tex]
Force = 100 Newton
Myra kicked the stone with an initial speed of 8.15 m/s at an angle of 30° above the horizontal.
a. Determine the horizontal and vertical components of the velocity of the projectile.
b. How far has the object traveled in 2.1 s?
c. How high has the object reached in 2.1 s?
Grade 9 Science (Serious Answers Please)
Answer:Its B
Explanation:Trust Me i done This Before
what revovles around the sun and is made out of rock,ice,gas,and dust?
Answer:
Comets are cosmic snowballs of frozen gases, rock and dust that orbit the Sun. When frozen, they are the size of a small town. When a comet's orbit brings it close to the Sun, it heats up and spews dust and gases into a giant glowing head larger than most planets.Hope this is fine for you,,!!The process of recovering valuable or useful materials from waste or scrap is called
a.
recycling.
c.
rebuilding.
b.
renewing.
d.
reducing.
Please select the best answer from the choices provided
A
B
C
D
Answer:
hi
Explanation:
А______
is a unit of measurement for energy. (7 Letters)
Answer:
Joule or kilowatt/hour