Acceleration

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

• 24 m/s²
• 18 m/s²
• 16 m/s²
• 16 m/s

Acceleration is defined as the CHANGE in 

• time it takes for one place to move to another place. 
• velocity of an object.
• distance divided by the time interval 
• velocity divided by the time interval 

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  

Acceleration only takes place when things speed up. 

• True
• False

In each of the following cases, determine where the car has no acceleration ?

• A car shortly after a stoplight turns green.
• A car approaching a red light
• A car with the cruise control set at 80 km/h
• A car turning a curve at a constant speed

Which of the following is a unit for acceleration?

• km/s
• m/s²
• mi/hr
• ft

A car turns right without slowing down. Is this an example of acceleration?

• No, acceleration is the increase or decrease in speed.

• Yes, because the car changed directions.

• Yes, because the car increased it's speed.

• No, because the car did not change directions.

When are you undergoing an acceleration in a car? 

• speed up
• slow down
• make turns
• All of the above 

How can acceleration be zero?

• a car runs out of gas and slowly rolls to a stop
• a car decreases speed at a constant rate until it comes to rest
• car has constant speed and is traveling on a straight path
• the car travels round trip and is back at the starting point

A dog runs with an initial speed of 7.5 m/s on a waxed floor. It slides to a stop in 15 seconds. What is the acceleration?

• +7.5 m/s2

• -7.5 m/s²

• -0.5 m/s²

• +0.5 m/s²