Physics Test 1 (ch 1-6)

A constant net force acts on an object. Which of the following best describes the object's motion? The object is moving with a decreasing acceleration. The object is moving with a constant velocity. The object is at rest; its position is constant. The object is moving with a constant acceleration. The object is moving with an increasing acceleration.

The object is moving with a constant acceleration.

An object is moving in the absence of a net force. Which of the following best describes the object's motion?

The object will continue to move with a constant velocity.

If the net work done on an object is zero, what can you determine about the object's kinetic energy? The object's kinetic energy remains the same. The object's kinetic energy is decreasing. The object's kinetic energy is increasing. The object's kinetic energy is zero.

The object's kinetic energy remains the same.

A swimmer is determined to cross a river that flows due south with a strong current. Initially, the swimmer is on the west bank desiring to reach a camp directly across the river on the opposite bank. In which direction should the swimmer head?

The swimmer should swim northeast.

A football player kicks a football in a field goal attempt. When the football reaches its maximum height, what is the relationship between the direction of the velocity and acceleration vectors? Assume air resistance is negligible.

At the maximum height, the velocity and acceleration vectors are perpendicular to each other.

An object moves in a circular path at a constant speed. What is the relationship between the directions of the object's velocity and acceleration vectors?

The velocity and acceleration vectors are perpendicular.

For general projectile motion, which of the following best describes the vertical component of a projectile's acceleration? Assume air resistance is negligible

The vertical component of a projectile's acceleration remains a nonzero constant.

A graph depicts force versus position. What represents the work done by the force over the given displacement? Work cannot be determined from this type of graph. The work done is equal to the area under the curve. The work done is equal to length of the curve. The work done is equal to the slope of the curve. The work done is equal to the product of the maximum force times the maximum position.

The work done is equal to the area under the curve.

A ball is thrown straight upward. How does the sign of the work done by gravity while the ball is traveling upward compare with the sign of the work done by gravity while the ball is traveling downward? Work done by gravity is negative while the ball is traveling upward and positive while the ball is traveling downward. Work done by gravity is positive while the ball is traveling upward and negative while the ball is traveling downward. Work done by gravity is positive while the ball is traveling both upward and downward. Work done by gravity is negative while the ball is traveling both upward and downward.

Work done by gravity is negative while the ball is traveling upward and positive while the ball is traveling downward.

a downward force of gravity on a book on a table has a reaction of a

force exerted on the earth by the book upward

A motorcycle drives up a steeply inclined ramp. The work done on the motorcycle by the Earth's gravitational force is ____.

neg

An object is moving with constant velocity. Which of the following best describes the force(s) acting on the object?

net force is zero

Two identical cars are driving in opposite directions at the same speed. Their kinetic energies have ____. different magnitudes, but the same sign the same magnitude and sign the same magnitude, but opposite signs different magnitudes and opposite signs

same mag and sign

An object cannot remain at rest unless

the net force exerted on it is zero.

During a certain time interval, the net work done on an object is zero joules. We can be certain that ____.

the object's final speed was the same as its initial speed

A person applies a 50 N force on a crate, causing it to move horizontally at a constant speed through a distance of 10 m. What is the net work done on the crate?

zero joules

If a car is moving to the left with constant velocity, one can conclude that the net force exerted on the car is

zero.

For a projectile launched horizontally, which of the following best describes the downward component of a projectile's velocity? Assume air resistance is negligible.

The downward component of the projectile's velocity continually increases.

For general projectile motion, which of the following best describes the horizontal component of a projectile's acceleration? Assume air resistance is negligible.

The horizontal component of a projectile's acceleration is zero.

For general projectile motion, which of the following best describes the horizontal component of a projectile's velocity? Assume air resistance is negligible.

The horizontal component of a projectile's velocity remains a nonzero constant.

A packing crate is sitting at rest on an inclined loading ramp. How does the magnitude of the force of static friction compare to the other forces acting on the crate?

The magnitude of the force of static friction is equal to the magnitude of the component of the weight of the crate parallel to the inclined ramp.

An object is hanging by a string from the ceiling of an elevator. The elevator is slowing down while moving upward. What is the magnitude of the tension in the string?

The magnitude of the tension in the string is less than the magnitude of the weight of the object.