Question 1

An object is moving with constant non-zero velocity. Which of the following statements about it must be true?

Accepted Answer

A) A constant force is being applied to it in the direction of motion. 
B) A constant force is being applied to it in the direction opposite of motion. 
C) A constant force is being applied to it perpendicular to the direction of motion. 
D) The net force on the object is zero. 
E) Its acceleration is in the same direction as it velocity. 
A) A constant force is being applied to it in the direction of motion. 
B) A constant force is being applied to it in the direction opposite of motion. 
C) A constant force is being applied to it perpendicular to the direction of motion. 
D) The net force on the object is zero. 
E) Its acceleration is in the same direction as it velocity.

Question 2

When a 45-kg person steps on a scale in an elevator, the scale reads a steady 410 N. Which of the following statements must be true? (There could be more than one correct choice.)

Accepted Answer

A) The elevator is accelerating upward at a constant rate. 
B) The elevator is accelerating downward at a constant rate. 
C) The elevator is moving upward at a constant rate. 
D) From the given information, we cannot tell if the elevator is moving up or down. 
A) The elevator is accelerating upward at a constant rate. 
B) The elevator is accelerating downward at a constant rate. 
C) The elevator is moving upward at a constant rate. 
D) From the given information, we cannot tell if the elevator is moving up or down.

Question 3

A fireman is sliding down a fire pole. As he speeds up, he tightens his grip on the pole, thus increasing the vertical frictional force that the pole exerts on the fireman. When the force on his hands equals his weight, what happens to the fireman?

Accepted Answer

A) The fireman comes to a stop. 
B) The fireman descends with slower and slower speed. 
C) The fireman descends with a smaller but non-zero acceleration. 
D) The fireman continues to descend, but with constant speed. 
E) The acceleration of the fireman is now upward. 
A) The fireman comes to a stop. 
B) The fireman descends with slower and slower speed. 
C) The fireman descends with a smaller but non-zero acceleration. 
D) The fireman continues to descend, but with constant speed. 
E) The acceleration of the fireman is now upward.

Question 4

A 75-N box rests on a perfectly smooth horizontal surface. The minimum force need to start the box moving is

Accepted Answer

A) 75 N. 
B) 7.5 N. 
C) 750 N. 
D) any horizontal force greater than zero. 
A) 75 N. 
B) 7.5 N. 
C) 750 N. 
D) any horizontal force greater than zero.

An object is moving with constant non-zero velocity. Which of the following statements about it must be true?

When a 45-kg person steps on a scale in an elevator, the scale reads a steady 410 N. Which of the following statements must be true? (There could be more than one correct choice.)

A fireman is sliding down a fire pole. As he speeds up, he tightens his grip on the pole, thus increasing the vertical frictional force that the pole exerts on the fireman. When the force on his hands equals his weight, what happens to the fireman?

A 75-N box rests on a perfectly smooth horizontal surface. The minimum force need to start the box moving is

Representing Motion

Motion in One Dimension

Vectors and Motion in Two Dimensions

Applying Newtons Laws

Gravity

Rotational Motion

Equilibrium Ad Elasticity

Momentum

Energy and Work

Using Energy

Thermal Properties of Matter

Fluids

Oscillations

Traveling Waves and Sound

Superposition and Standing Waves

Wave Optics

Ray Optics

Optical Instruments

Electric Fields and Forces

Electric Potential

Current and Resistance

Circuits

Magnetic Fields and Forces

Em Induction and Em Waves

Ac Electricity

Relativity

Quantum Physics

Atoms and Molecules

Nuclear Physics

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Exam 4: Forces and Newtons Laws of Motion

An object is moving with constant non-zero velocity. Which of the following statements about it must be true?

When a 45-kg person steps on a scale in an elevator, the scale reads a steady 410 N. Which of the following statements must be true? (There could be more than one correct choice.)

A fireman is sliding down a fire pole. As he speeds up, he tightens his grip on the pole, thus increasing the vertical frictional force that the pole exerts on the fireman. When the force on his hands equals his weight, what happens to the fireman?

A 75-N box rests on a perfectly smooth horizontal surface. The minimum force need to start the box moving is

Representing Motion

Motion in One Dimension

Vectors and Motion in Two Dimensions

Applying Newtons Laws

Gravity

Rotational Motion

Equilibrium Ad Elasticity

Momentum

Energy and Work

Using Energy

Thermal Properties of Matter

Fluids

Oscillations

Traveling Waves and Sound

Superposition and Standing Waves

Wave Optics

Ray Optics

Optical Instruments

Electric Fields and Forces

Electric Potential

Current and Resistance

Circuits

Magnetic Fields and Forces

Em Induction and Em Waves

Ac Electricity

Relativity

Quantum Physics

Atoms and Molecules

Nuclear Physics

Filters