Respuesta :

Answer: h = 14 m

Explanation:

From the information given,

weight of rocket = 10N

Recall, weight = mg

Thus, mg = 10

where

m = mass of object

g = acceleration due to gravity and its values is 9.8 m/s^2

At the exact top of the trajectory, the total mechanical energy = 140 J

Recall,

total mechanical energy = kinetic energy + potential energy

At the exact top, kinetic energy = 0

Thus,

140 = potential energy

Recall, potential energy = mgh

where h is the height of the object(in this case, h is the height at the exact top and its value is 140J). Thus,

140 = mgh

Substituting mg = 10, we have

140 = 10h

h = 140/10

h = 14 m