Motion in One Dimension

One drop of oil falls straight down onto the road from

the engine of a moving car every 5 s. Figure OQ2.1

shows the pattern of the drops left behind on the pavement.

What is the average speed of the car over this

section of its motion?

• 20 m/s

• 24 m/s

• 30m/s

• 100 m/s

• 120 m/s

A racing car starts from rest at t = 0 and reaches a

final speed v at time t. If the acceleration of the car

is constant during this time, which of the following

statements are NOT true?

• The car travels a distance vt.

• The average speed of the car is v/2.

• The magnitude of the acceleration of the car is v/t.

• The velocity of the car remains constant.

• None of statements (a) through (d) is true.

A juggler throws a bowling pin straight up in the air.

After the pin leaves his hand and while it is in the air,

which statement is true?

• The velocity of the pin is always in the same direction as its acceleration.

• The velocity of the pin is never in the same direction as its

  acceleration.

• The acceleration of the pin is zero.

• The velocity of the pin is opposite its acceleration

  on the way up.

• The velocity of the pin is in the same direction as its acceleration on the way up.

When applying the equations of kinematics for an

object moving in one dimension, which of the following

statements must be true?

• The velocity of the object must remain constant.

• The acceleration of the object must remain constant.

• The velocity of the object must increase with time.

• The position of the object must increase with time.

• The velocity of the object must always be in the same direction as its acceleration.

A cannon shell is fired straight up from the ground at an

initial speed of 225 m/s. After how much time is the shell

at a height of 6.20 x 10^2 m above the ground and moving

downward?

• 2.96 s

• 17.3 s

• 25.4 s

• 33.6 s

• 43.0 s