Amount of force a motor can make in 35s

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An electric motor exerts force while lifting a loaded elevator, developing 65kW of power over a distance of 17.5 m in 35 seconds. The challenge lies in calculating the force without knowing the mass, as the standard force equation requires mass and acceleration. Power can be related to force and velocity, suggesting a formula that incorporates these variables. The discussion emphasizes deriving an equation that allows for the elimination of mass by introducing an unknown variable. Ultimately, understanding the relationship between power, force, and velocity is key to solving the problem.
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Homework Statement


An electric motor develops 65kW of power as it lifts a loaded elevator 17.5 m in 35s. How much force does the motor exert?
Acceleration: .5

Homework Equations


F equals mass times acceleration

The Attempt at a Solution


Ok so I tried to find mass but when the equation was m equals N divided m/s(squared) but there isn't a weight there. Also I tried the force equation but I can't do that without mass...
[/B]
 
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PsychoSya said:

Homework Statement


An electric motor develops 65kW of power as it lifts a loaded elevator 17.5 m in 35s. How much force does the motor exert?
Acceleration: .5

Homework Equations


F equals mass times acceleration

The Attempt at a Solution


Ok so I tried to find mass but when the equation was m equals N divided m/s(squared) but there isn't a weight there. Also I tried the force equation but I can't do that without mass...[/B]
Power is measured in units of watts, which is a derived unit in the SI system. You are given a distance traveled by the elevator and a time in which to do this, which suggests a certain velocity for the elevator. Is there a formula for power which you can derive that uses force and velocity. Hint: look at the units of each quantity.
 
PsychoSya said:

Homework Statement


An electric motor develops 65kW of power as it lifts a loaded elevator 17.5 m in 35s. How much force does the motor exert?
Acceleration: .5

Homework Equations


F equals mass times acceleration

The Attempt at a Solution


Ok so I tried to find mass but when the equation was m equals N divided m/s(squared) but there isn't a weight there. Also I tried the force equation but I can't do that without mass...[/B]
Don't be put off by such matters. Just invent an unknown m for the mass and see if you can get enough equations to eliminate it later.
 
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