Speed, Acceleration, Motion HW

The rate that a car's velocity changes is its

• speed

• force

• gravity

• acceleration

Acceleration is defined as the CHANGE in 

• the time it takes for one place to move to another place. 

• the mass of an object divided by the time interval.

• the distance divided by the time interval 

• the velocity divided by the time interval 

A negative acceleration means that an object is _____. 

• not accelerating
• not moving
• speeding up 
• slowing down 

A roller coaster accelerates from an initial speed of 6.0 m/s to a final speed of 70 m/s over 4 seconds. What's the acceleration?

• 24 m/s²

• 18 m/s²

• 16 m/s²

• 16 m/s

A drag racer accelerated from 0 m/s to 200 m/s in 5 s.  What was the acceleration?

• 0 m/s
• 40 m/s²
• -40 m/s²
• 40 m/s

In which of the following cases does a car have zero acceleration?

• A car speeding up after a stoplight turns green.

• A car slowing down when it approaches a stop sign.

• A car set on cruise control so that is maintains 45 mi/hr.

• A car turning a curve at a constant speed.

Which of the following is an example of deceleration?

• a car approaching a stop sign and slowing down

• a plane increasing speed down the runway and then taking flight

• a roller coaster moving down a steep hill 

• an airplane cruising in a straight flight plan

Why does a car accelerate as it round a corner at a constant speed?

• Its direction changes
• It doesn't
• It slows down
• Its speeds up  

The SI unit for acceleration is

• mph
• ft/sec²
• m/s²

When are you undergoing an acceleration in a car? 

• When the car speeds up.

• When the car slows down.

• When the car makes a turn.

• All of the above