Physics Final Exam Practice Quizzes 2.1,3.1,3.2, 6.1,6.2,6.3

10.0 m/s

A 1710 kg minivan is known to have 86000.0 J of kinetic energy. What is the velocity of the vehicle?

0.42 J

A 4.1 g rubber band with a spring constant of 29 N/m is stretched 0.17 m. How much elastic potential energy is stored by the rubber band?

0 m/s2

A 5 kg object is moving at a constant velocity of 15 m/s. What is its acceleration?

19.684 m/s

A boat with a kinetic energy of 313255 J has a mass of 1617.0 kg. What is the velocity of the boat?

15 kg

A box is pushed with a force of 37 N across a frictionless surface, causing it to accelerate at a rate of 2.53 m/s2. What is the mass of the box?

0.49 m

A box slides down the ramp of an assembly line and compresses a spring. If the 14.5 kg box compresses the spring by 0.412 m, what was the height of the ramp? Assume no energy was lost due to friction and that the spring constant was 821 N/m.

1160 kg

A car on the highway begins to speed up at a rate of 6.12 m/s2. The net force on the car is 7070 N. What is the car's mass?

9800 N/m

A child bounces on a pogo stick, compressing the spring 0.11 m with every bounce. If the compressed spring stores 59 J of elastic potential energy, what is the spring constant of the pogo stick?

2600 J

A diver with a mass of 68 kg is standing on a diving board 3.9 m above the water. What is the gravitational potential energy of the diver with respect to the water?

0.0 N

A force of 8.8 N is used to pull a wagon with a constant velocity. The mass of the wagon is 4.5 kg. What is the net force acting on the wagon?

0.0 N

A mover pushes a 15 kg box with a force of 59 N to slide it across the floor. The box is moving at a constant velocity. What is the net force on the box?

50 J

A runner initially has 260 J of kinetic energy, but then speeds up and has 310 J of kinetic energy. How much work was required for this change?

48 kg

A runner nearing the finish line begins to accelerate at a rate of 1.28 m/s2. The net force acting on the runner between her shoes and the ground is 61 N. What is the mass of the runner?

3.6 Watts

A toy car has a mass of 22.7 kg. It is driven, starting from rest, at a constant acceleration of 0.51 m/s2 for 44.0 seconds. It travels a distance of 13.7 m, then crashes into a wall and the engine dies. How much power had the car\'s engine used to propel the car before hitting the wall?

39 J

Consider a 2.10 kg box sliding down a ramp. The box starts from rest at a maximum height of 9.40 meters with a gravitational potential energy of 193 J. As the box slides down the ramp it gains kinetic energy. Neglecting the effects of friction and air resistance, calculate the gravitational potential energy of the box when the kinetic energy is 154 J.

The book pushes down on the desk and the desk pushes up on the book.

Consider a situation where a book is resting on a desk. Select the statement that represents a force pair present in this situation.

C

Consider the path of the roller coaster shown below. Assume there are no external forces such as friction or air resistance acting on the car and that it is at rest at point A. At what point along the path does the roller coaster have the maximum amount of kinetic energy?

12.2 kg

Gino rolls a ball with a force of 55.0 N, and it accelerates at 4.50 m/s2. If friction is ignored, what must the mass of the ball be?

121 J

Gravity does 347 J of work while a rock rolls down a hill. If its final kinetic energy was 468 J what would be the value of the initial kinetic energy of the rock?

1178 J

How much work would have been done by a scooter if the kinetic energy of the scooter went from 255 J to 1433 J?

756 J

If 335 J of work is done on a soccer ball with an initial kinetic energy of 421 J, what would be the final kinetic energy of the soccer ball?

45 m at an angle 27° east of north

If you walk 40 m to the north, then turn and walk 20 m to the east, how far away are you from where you started?

The dynamic cart had the largest acceleration in trial 4.

In each of the trials in the data table, a dynamic cart was subjected to a different force. The mass of the dynamic cart remained the same in each trial. Trial Force (N) 1 100 2 20 3 50 4 200 What can you conclude about the acceleration of the cart in each trial?

More power is delivered rolling down the left side.

In the distance you see a hill. From your perspective the hill has a left and right side. The left side of the hill has a steeper slope than the right. On top of the hill is a man and a boulder. He will choose one side of the hill to roll the boulder down to the bottom. Which of the following is true about the power delivered to the boulder at the bottom that is at the same altitude on both sides? Neglect any friction

31.2 J

Jared is a cliff diver that jumps into water from an extreme distance. He usually throws a rock ahead of him to break the surface tension of the water allowing him cleaner entry into the water. Calculate the total mechanical energy of a 2.61 kg rock traveling 1.71 m/s, when it is 1.07 m above the water.

Hang two scales side by side from the same height. Hang the object from both scales at the same time and add the two readings to get the weight.

Lucas is trying to find the weight of an object, but all he has are three 500 N spring scales. When he places the object on a single spring scale, the indicator on the scale shows that the object exceeds the range of the scale. How should Lucas weigh the object?

a ball tossed up into the air returning to the ground

Newton's third law describes the nature of force pairs. He stated that when an object exerts force on another object, the second object exerts the same force back in the opposite direction simultaneously. Which is NOT an example of a force pair?

Motors A and B produce equal amounts of power.

Suppose you want to use a motorized system to move an elevator up at a certain rate. You have to decide between two motors, Motor A and Motor B. Motor A exerts force equal to the elevator\'s weight at capacity and moves the elevator twice as fast as motor B. Motor B exerts twice the force as motor A, but will move the elevator half as fast as motor A. Which of the following is true of the powers produced by Motor A and Motor B?

Vector B

The diagram shows vectors representing some possible forces exerted on a wheelbarrow being held still on a ramp.

A = 40.0 N up, B = 10.0 N right

The given free-body diagram shows four forces acting on an object. Force C in the free-body diagram is 40.0 N down. Force D is 75.0 N to the left. The net force on the object is 65.0 N to the left. Determine the missing values for vectors A and B.

If both the mass and the velocity of the vehicle double, the kinetic energy will increase by a factor of eight.

The table below shows data collected for some vehicles on the road. What conclusion can be drawn about the relationship between mass, velocity, and kinetic energy?

The ball is rolled across a smoother surface and continues for a greater distance. The second student concludes that friction is an external force preventing the motion of the ball.

Two physics students are debating the law of inertia. The first student believes the law of inertia is incorrect because objects in motion cannot stay in motion unless there is an unbalanced force applied. The first student gives an example of a ball eventually coming to rest when rolled across a field of grass. The first student concludes that the lack of unbalanced forces is causing the ball to stop, since there are no unbalanced forces keeping it in motion. Which experiment, if performed by the second student, provides the best evidence and strongest conclusion supporting the law of inertia?

Object 2 is moving faster than Object 1

Using the data table provided, determine which of the following is not a valid conclusion that can be drawn.

230000 J

What is the kinetic energy of a bullet with a mass of 0.36 kg and a velocity of 1140 m/s?

220 N/m

When a force of 35 N is applied to a spring it is compressed 0.16 m. What is the spring constant of the spring?

Vector quantities have magnitude and direction, whereas scalar quantities only have magnitude.

Which best describes the difference between scalar and vector quantities?

a support force that acts perpendicular to the surface an object is resting on

Which best describes the normal force?

potential energy of a spring that is stretched or compressed

Which of the choices below is the best definition of elastic potential energy?

the rate at which work is done over time

Which of the choices below is the best definition of power?

when a force displaces an object in the same direction as the force is applied

Which of the choices below is the best description of work?

the type of energy that objects in motion have

Which of the following best defines kinetic energy?

accomplishing the same amount of work with less applied force or applying a force over a smaller distance

Which of the following best describes the benefit of mechanical advantage?

increasing its mass or its height

Which of the following changes will always increase an object\'s gravitational potential energy?

The work on an object can be determined by subtracting the initial kinetic energy from the final kinetic energy.

Which of the following is a correct description of the work-energy theorem?

As a sled coasts up a steep snowy hill, more and more energy is destroyed until the sled stops.

Which of the following statements violates, or does not follow, the law of conservation of energy? Assume that all scenarios occur in an ideal system.

a quantity that has a magnitude and direction

Which of the options is the best definition of a vector?

mass

Which of the options is the best example of a scalar quantity?

direction

Which of the pieces of information cannot be determined from a scalar quantity?

mass

Which of these properties determines the amount of inertia an object has?