What force does a trampoline have to apply to a 43.0–kg gymnast to accelerate her straight up at 7.30 m/s2? Note that the answer is independent of the velocity of the gymnast–she can be moving either up or down, or be stationary.
- Wayne DeguManLv 71 month agoFavorite Answer
Resolving vertically and using F = ma we have:
F - mg = ma
so, F = m(g + a)
Then, F = 43(9.8 + 7.3) => 735 Newtons
- Anonymous1 month ago
There are two forces on the gymnast when she is in contact with the trampoline: her weight (mg) and the force from the trampoline (T). Resultant force F = T + mg.
Using F = ma gives: T + mg = ma
T = ma - mg = m(a - g)
Taking up as positive, down as negative gives:
T = m(a - g) = 43.0(7.30 - (-9.81)) =736N (upwards).