Question

A kickball at the top of a hill is nudged so it begins rolling down the hill. The slope of the hill causes the ball to accelerate at 1.3 m/s². How fast is the ball rolling at the end of 7.0 seconds when it reaches the bottom of the hill?

a. -9.1 m/s
b. 0.19 m/s
c. 9.1 m/s
d. 8.3 m/s

Answer 1

The final velocity of the kickball after 7.0 seconds rolling down the hill with an acceleration of 1.3 m/s² is 9.1 m/s.

Step-by-step explanation:

The student's question involves calculating the final velocity of a ball rolling down a hill with a constant acceleration due to the slope of the hill. Using the linear motion equation v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration, and t is the time, we can determine how fast the ball is moving after 7.0 seconds when it reaches the bottom of the hill.

As the ball is nudged, we can assume the initial velocity u is 0 m/s. Applying the values given: v = 0 m/s + (1.3 m/s²)(7.0 s) which equals 9.1 m/s. Therefore, the correct answer is (c) 9.1 m/s.