Physics Quiz: Final Exam 23-24 Semester 1

Which of the following is true for a perfectly inelastic collision?

• The objects stick together after they collide

• Each object has its own, different velocity after the objects collide

• The objects travel separately after they collide

• Both A and B are correct

A cart is rolling along a frictionless, horizontal surface. Which of the following describes the motion of the cart as it continues to roll along the surface?

• The cart will slow down as it runs out of the forward force.

• The cart will continue to roll with constant speed.

• The cart will continue to roll with constant speed only if it is rolling downhill.

• The cart will slow down as it uses up its speed.

If a cart is traveling with acceleration, what conclusions can be drawn about the forces acting on the cart?

• The cart must be frictionless.

• The cart must be rolling downhill.

• The cart must have a net unbalanced force acting on it.

• No force is needed; the cart will naturally slow down.

A student wants to set up an experiment to determine the effect of a net force on an object's acceleration. To do this, she should:

• vary the force acting on the object and the mass of the object at the same time.

• vary the mass of the object, but not the force acting on the object.

• vary the force acting on the object, but not the object's mass.

• keep both the force acting on the mass and the mass of the object constant as it rolls along a horizontal surface.

A 2-kg block is dropped from the roof of a tall building at the same time a 6-kg ball is thrown horizontally from the same height. Which statement best describes the motion of the block and the motion of the ball? (Disregard air resistance.)

• The 2-kg block hits the ground first because it has no horizontal velocity (side to side).

• The 6-kg ball hits the ground first because it has more mass.

• The 6-kg ball hits the ground first because it is round.

• The block and the ball hit the ground at the same time because they have the same vertical acceleration (up and down).

A pitching machine launches a baseball horizontally (sideways) with no spin with a constant force. Which of the following statements correctly what would happen if a more massive ball is put into the machine?

• The ball's acceleration increases because the object's mass increased

• The ball's acceleration remains the same because the same amount of force is being applied

• The ball's acceleration decreases because the object's mass increased

• The ball's acceleration remains the same because mass does not matter for acceleration and force

A student is holding a book that has a force of 20 N towards the ground in his hand while sitting in a chair. If the book remains at rest, which of the following is true?

• The forces are unbalanced due to gravity working upwards

• The forces are balanced due to an applied force working upwards

• The forces are unbalanced due to friction force working upwards

• The forces are balanced due to a normal force working downwards

Two students have a "tug-of-war" on a smooth gym floor. One student has a mass of 70 kg and is wearing socks, but no athletic shoes. The other student has a mass of 60 kg and is wearing athletic shoes. The student most likely to win will be:

• the 60-kg student because he can pull harder on the 70-kg student.

• the 70-kg student because he can pull harder on the 60-kg student.

• the 60-kg student because he experiences a greater frictional force with the floor.

• the 70-kg student because he experiences a greater frictional force with the floor.

Which of the following safety features were the most recently added to vehicles?

• Seat belts

• Turn signals

• Air bags

• Backup sensing system

A student exerts a force of 100 N to accelerate the bike over a distance of 20 meters. What is the amount of work done on the bike?

• 5 J

• 0.2 J

• 200 J

• 2000 J