# physics

posted by .

A fully loaded, slow-moving freight elevator has a cab with a total mass of 1800 kg, which is required to travel upward 50 m in 2.6 min, starting and ending at rest. The elevator's counterweight has a mass of only 780 kg, so the elevator motor must help pull the cab upward. What average power is required of the force the motor exerts on the cab via the cable?

• physics -

average velocity = 50m/156 s
= 0.3205 m/s
average force required = (1800 - 780)kg*9.81 m/s^2 = 10,006 N
Power (average) = force x velocity = 3207 W = 4.3 horsepower

The power will need to be higher during acceleration, and lower during deceleration, but 4.3 Hp is the average needed.

## Similar Questions

1. ### physics

A loaded elevator with very worn cables has a total mass of 1800 kg and the cavles can withstand a maximusm tension of 28000N a) What is the maximum upward acceleration for the elevator if the cables are not to brake?
2. ### Physics

A fully loaded, slow-moving freight elevator has a cab with a total mass of 1250 kg, which is required to travel upward 58 m in 3.4 min, starting and ending at rest. The elevator's counterweight has a mass of only 1005 kg, and so the …
3. ### Physics

fully loaded, slow-moving freight elevator has a cab with a total mass of 1250 kg, which is required to travel upward 58 m in 3.4 min, starting and ending at rest. The elevator's counterweight has a mass of only 1005 kg, and so the …
4. ### physics

A woman stands on a scale in a moving elevator. Her mass is 57.0 kg, and the combined mass of the elevator and scale is an additional 811 kg. Starting from rest, the elevator accelerates upward. During the acceleration, the hoisting …
5. ### Physics

A woman stands on a scale in a moving elevator. Her mass is 56.0 kg, and the combined mass of the elevator and scale is an additional 809 kg. Starting from rest, the elevator accelerates upward. During the acceleration, the hoisting …
6. ### physics

A woman stands on a scale in a moving elevator. Her mass is 69.1 kg, and the combined mass of the elevator and scale is an additional 734 kg. Starting from rest, the elevator accelerates upward. During the acceleration, the hoisting …
7. ### physics

A woman stands on a scale in a moving elevator. Her mass is 68.0 kg, and the combined mass of the elevator and scale is an additional 713 kg. Starting from rest, the elevator accelerates upward. During the acceleration, the hoisting …
8. ### PHYSICS

WORKER ARE LOADING EQUIPMENT INTO A FREIGHT ELEVATOR AT THE TOP FLOOR OF A BUILDING HOWEVER THEY OVERLOAD THE ELEVATORAND THE WORN CABLE SNAPS THE MASS OF THE LOADED ELEVATOR AT THE TIME OF THE ACCIDENT IS 1600KG..AS THE ELEVATOR FALLS,THE …
9. ### physics

A woman stands on a scale in a moving elevator. Her mass is 65.0 kg, and the combined mass of the elevator and scale is an additional 757 kg. Starting from rest, the elevator accelerates upward. During the acceleration, the hoisting …
10. ### Physics

A woman stands on a scale in a moving elevator. Her mass is 65.0 kg, and the combined mass of the elevator and scale is an additional 757 kg. Starting from rest, the elevator accelerates upward. During the acceleration, the hoisting …

More Similar Questions