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KMjuniormint5
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[SOLVED] An Elevator and work
The loaded cab of an elevator has a mass of 3.0 103 kg and moves 204 m up the shaft in 23 s at constant speed. At what average rate does the force from the cable do work on the cab? Answer in kW.
Power is the dot product of the force and velocity
Fnet = ma
I went about this problem by since Power is the dot product of velocity and the force.
The force would be Tension - W = ma and since ma = 0. tension = W = mg so there is your force m*g
then i take 204m/23s to get the velocity of 68 m/s so. . .
mg*68 to give you the power in watts but since they want the velocity in kW, you divide by 1000 to get to that desided amount. . .
am I going about this problem correctly?
Homework Statement
The loaded cab of an elevator has a mass of 3.0 103 kg and moves 204 m up the shaft in 23 s at constant speed. At what average rate does the force from the cable do work on the cab? Answer in kW.
Homework Equations
Power is the dot product of the force and velocity
Fnet = ma
The Attempt at a Solution
I went about this problem by since Power is the dot product of velocity and the force.
The force would be Tension - W = ma and since ma = 0. tension = W = mg so there is your force m*g
then i take 204m/23s to get the velocity of 68 m/s so. . .
mg*68 to give you the power in watts but since they want the velocity in kW, you divide by 1000 to get to that desided amount. . .
am I going about this problem correctly?