Question

select the correct answer from each drop - down menu. a ball starts from rest. it rolls down a ramp and reaches the ground after 4 seconds. its final velocity when it reaches the ground is 7.0 meters/second. the initial velocity of the ball is meters/second, and its acceleration is meters/second²

Explanation:

Step1: Determine initial velocity

The ball starts from rest, so initial velocity $u = 0$ m/s.

Step2: Calculate acceleration

Use the formula $v=u + at$, where $v$ is final - velocity, $u$ is initial velocity, $a$ is acceleration and $t$ is time. Given $v = 7$ m/s, $u = 0$ m/s and $t = 4$ s. Rearranging the formula for $a$ gives $a=\frac{v - u}{t}$. Substitute the values: $a=\frac{7 - 0}{4}=\frac{7}{4}=1.75$ m/s².

Answer:

Initial velocity: 0 meters/second
Acceleration: 1.75 meters/second²