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2 years ago

A helicopter pulls upward by means of a rope on a 250 kg crate to lift it UNIFORMLY. What is the net force on the crate?

Physics

1 answer:

Cloud [144]2 years ago

3 0

Answer:

The net force = 0

Explanation:

The given information includes;

The mass of the crate = 250 kg

The way the helicopter lifts the crate = Uniformly (constant rate (speed), no acceleration)

In order to pull the crate upwards, the helicopter has to provide a force equivalent to the weight of the crate keeping the helicopter on the ground.

The weight of the crate = The mass of the crate × The acceleration due gravity acting on the crate

The weight of the crate, $F_w$ ↓ = 250 kg × 9.81 m/s² = 2,452.5 N

The force the helicopter should provide to just lift the crate, $F_{(helicopter)}$ ↑ = The weight of the crate = 2,452.5 N

The net force, $F_{(net)}$ = $F_{(helicopter)}$ ↑ - $F_w$ ↓ = 2,452.5 N - 2,452.5 N = 0

The net force = 0.

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