Arock hits the ground at a speed of 15 m/s and leaves a hole 50 cm deep. after it hits the ground, what is the magnitude of the rock's (assumed)uniform acceleration? a) 112.5 m/s^2
b) 225 m/s^2
c) 225
d) 127.5 m/s^2

B) 225 m/s^2

Explanation:

The rock hits the ground at 15m/s and travels 50cm=0.5m through the ground until it stops.

The acceleration is supposed to be uniform, so the formula we have to use is , which for acceleration is:

Taking the downwards direction as positive (the direction of traveling, so the initial velocity and displacement will be positive), substituting our values for that movement we have:

Where the negative sign indicates that it is pointing upwards.

nah.   i'm just sleepy.

he made 11 calls in one day