Quiz 01

Suppose that an object is moving with constant nonzero acceleration. Which of the following is an accurate statement concerning its motion?

In equal times its velocity changes by equal amounts.

If the vertical sum of vectors A and B is equal to zero, then the two vectors have equal magnitudes and are directed in the same direction.

False

A ball is thrown directly upward and experiences no air resistance. Which one of the following statements about its motion is correct?

The acceleration is downward during the entire time the ball is in the air.

Which of the following statements is a true statement?

The magnitude of a vector cannot be zero unless all of its components are zero.

The motions of a car and a truck along a straight road are represented by the velocity-time graphs in the figure. The two vehicles are initially alongside each other at time t = 0. At time T, what is true about these two vehicles since time t = 0?

The truck will have traveled further than the car.

For an object in uniform circular motion, its velocity and acceleration vectors are always perpendicular to each other at every point in the path.

True

The magnitude of a vector can never be less than the magnitude of one of its components

True

The figure shows the velocity of a particle as it travels along the x-axis. What is the direction of the acceleration at t = 0.5 s?

in the -x direction

For general projectile motion, when the projectile is at the highest point of its trajectory

its velocity is perpendicular to the acceleration

If an object travels at a constant speed in a circular path, the acceleration of the object is

larger in magnitude the smaller the radius of the circle.

The figure represents the velocity of a particle as it travels along the x-axis. At what value (or values) of t is the instantaneous acceleration equal to zero?

t= 1 s

While an object is in projectile motion (with upward being positive) with no air resistance

the horizontal component of its velocity remains constant and the vertical component of its acceleration is equal to -g.

Three vectors have equal magnitudes and make 120 degrees with each other. We can say that

the resultant is zero

The sum of two vectors has the greatest magnitude when the angle between those two vectors is

zero degrees