# Amount of force a motor can make in 35s

## 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...
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SteamKing
Staff Emeritus
Homework Helper

## 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.

haruspex
Homework Helper
Gold Member

## 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.