show that the acceleration is 7.5 m/s² for a ball that starts from rest and rolls down a ramp and gains a speed of 30 m/s in 4s
V = Vo + a*t = 30 m/s
0 + a*4 = 30
a = 30/4 = 7.5 m/s^2.
To show that the acceleration is 7.5 m/s² for a ball that starts from rest and rolls down a ramp, we can use the equation for acceleration:
acceleration (a) = (final velocity (v) - initial velocity (u))/time (t)
Given:
Initial velocity (u) = 0 m/s (starts from rest)
Final velocity (v) = 30 m/s
Time (t) = 4 s
Substituting the given values into the formula, we can calculate the acceleration:
a = (v - u)/t
= (30 m/s - 0 m/s)/(4 s)
= 30 m/s / 4 s
= 7.5 m/s²
Therefore, the acceleration of the ball rolling down the ramp is 7.5 m/s².