An elevator weighting 2500 N ascends at a constant speed of 8 m/s. How much power must the motor supply to do this?
To find the power that the motor must supply, we can use the equation:
Power = Force × Velocity
First, let's find the force exerted by the elevator. The force exerted by an object can be calculated using Newton's Second Law:
Force = Mass × Acceleration
Since the elevator is ascending at a constant speed, we know that its acceleration is zero. Therefore, the force exerted by the elevator is equal to its weight.
Given that the weight of the elevator is 2500 N, the force exerted by the elevator is 2500 N.
Now, we can substitute the force and velocity values into the equation for power:
Power = Force × Velocity
= 2500 N × 8 m/s
Calculating this, we find:
Power = 20,000 watts (or 20 kilowatts)
So, the motor must supply 20 kilowatts of power to lift the elevator at a constant speed of 8 m/s.