Topic 1.2: Practice Sheet — Acceleration

Name: _______________________________ Date: _______________ Period: ______

Directions: Show your work for every problem — a correct answer with no work shown earns partial credit at best. Circle or box your final answer.

Warm-Up Level (straightforward, one-step)

A car speeds up from 10 m/s to 30 m/s in 5 seconds. Find its acceleration.
A skateboarder slows from 8 m/s to 2 m/s in 3 seconds. Find the acceleration (include the correct sign).

A ball is thrown and its velocity changes from +12 m/s to −12 m/s (reverses direction entirely) over 2.4 seconds. Find the acceleration.
A rocket sled accelerates at 6 m/s² for 4 seconds, starting from rest. Find its final velocity.
A cyclist's velocity is 15 m/s. After applying the brakes with an acceleration of −3 m/s², how long will it take the cyclist to come to a complete stop?

A car's velocity goes from 0 to 25 m/s in 5 s (Interval A), then stays constant at 25 m/s for the next 5 s (Interval B), then drops from 25 m/s to 0 in 2.5 s (Interval C). a) Find the acceleration during each of the three intervals. b) Which interval has the largest-magnitude acceleration? Justify using your calculated values. c) A classmate says "Interval B has zero acceleration, so nothing is happening to the car during that time." Explain what's wrong with this statement — is the car really doing "nothing"?
An object's acceleration is −4 m/s² the entire time it's in the air after being thrown straight up. Explain why the acceleration doesn't become positive on the way back down, even though the object's velocity clearly changes from moving up to moving down.

Keep this sheet — it's part of your semester study materials, same as your Concept Sheets.