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## Homework Statement

You have an object of mass 6.154 kg on the surface of the moon. What force is required to propel the object vertically to a height of 100m?

acceleration due to gravity on the moon (g): 1.625 m/s^2

## Homework Equations

y = (v^2 - v0^2) / (2*g)

y: vertical displacement

v: velocity at displacement

v0: initial velocity

g: acceleration due to gravity

y = v0*t - (1/2)*g*t^2

t: time of flight

KE = (1/2)*m*v^2

KE: Kinetic energy

## The Attempt at a Solution

Weight of object on the moon is 6.154kg * 1.625 m/s^2 = 10 N.

Using the first equation above with v = 0 (apex of flight) and solving for v0, I find that the required initial velocity is 18.03 m/s.

The second equation gives a flight time of 22.19 seconds--11.095 seconds to apex and 11.095 seconds back to the surface.

The third equation yields a required kinetic energy needed of 988.25 J which is the same as the work required by the propulsion system because the object is initially at rest.

And this is where I get stuck. What equation do I use next? Power? How do I get the propulsive force required?

Thanks