Question

A hailstone traveling with a velocity of 43 meters/second comes to a virtual stop 0.28 seconds after hitting water. What is the magnitude of its acceleration in the water?
A. 12 meters/second2
B. 1.5 × 102 meters/second2
C. 78.6 meters/second2
D. 6.5 × 10-3 meters/second2

Answer 1

Answer:

The magnitude of its acceleration in the water is 1.5*10² meters/second²

Explanation:

Acceleration tells us how the speed changes. Therefore, it relates the changes in speed with the time it takes to produce. So

$acceleration=\frac{speed change}{time spent changing speed}$

The speed change is ending speed - starting speed. So in this case, the speed change is 0 - (43 m/s) = -43 m/s . [ You know that the hailstone travels with a speed of 43 meters / second (initial speed) and stops (final speed = zero) 0.28 seconds after hitting the water.]

And time spent changing speed is 0.28 seconds.

Considering the speed change module, that is the number regardless of the sign:

$acceleration=\frac{43 m/s}{0.28 s}$

acceleration=153.57 m/s²≅1.5*10² meters/second²

The magnitude of its acceleration in the water is 1.5*10² meters/second²

Answer 2

I think its "a". but im not sure.