Answer: >41.5N
Explanation:
Mass of bowling ball = 7.5kg
Breaking point of rope = T > 115N
Where T = Tension on the rope
Since the bowling ball is hung by a rope :
Tension (T) = mg = 7.5 kg × 9.8m/s^2 = 73.5kgm/s^2
T = mg + ma
F = ma
T = mg + F
>115 = 73.5 + F
F = 115 - 73.5
F = 41.5N
Force >41.5N
Action reaction when you push on the ground the ground pushes you back
2/5 = .4
.4*100= 40%
Alex spends more time
The first option.
The total mechanical energy before an action (which makes up PE and KE) equals the total mechanical energy after an action.
So
KEi + PEi = KEf + PEf