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3 years ago

A 110-pound person pulls herself up 4.0 feet. This took her 2.5 seconds. How much power was developed?

Physics

2 answers:

mrs_skeptik [129]3 years ago

5 0

Answer:

0.32 Hp is the answer. right

lesya [120]3 years ago

4 0

Answer: Power developed by her is <u><em>0.32 hp</em></u>

Explanation:

Work done , W= Force(F) X Displacement (d) in the direction of force

Thus work done , $W=Fd=110\times 4.0 ft-lbf = 440 ft-lbf$

Now 1.0 ft-lbf = 1.355 joules of energy

Therefore , work done, W= 440x 1.355 J = 596.2 J

Average Power , $P=\frac{work done(W)}{time (t)}$

=> $P=\frac{596.2}{2.5} watts = 238.5 watts$

We know 746 hp = 1.0 watts

=> $P=\frac{238.5}{746} hp=0.32 hp$

Thus average power developed by her is 0.32 hp

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3 0

3 years ago

Read 2 more answers

The acceleration due to gravity is 9.81 m/s2, towards the Earth. Rain falling from an altitude of 9,000 m would fall for about 1

Anna [14]

Answer:

the final speed of the rain is 541 m/s.

Explanation:

Given;

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height of fall of the rain, h = 9,000 m

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Determine the initial velocity of the rain, as follows;

$h = ut + \frac{1}{2} gt^2\\\\9000 = 90u + \frac{1}{2} (9.8)(90)^2\\\\9000 = 90u + 39690\\\\90u = -30690\\\\u = \frac{-30690}{90} \\\\u = -341 \ m/s$

The final speed of the rain is calculated as;

$v^2 = u^2 + 2gh\\\\v^2 = (-341)^2 + 2(9.8\times 9000)\\\\v^2 = 292681\\\\v = \sqrt{292681} \\\\v = 541 \ m/s$

Therefore, the final speed of the rain is 541 m/s.

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3 years ago

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Consider a cylindrical crew module with a diameter of 5 meters, a length of 15 meters, and a crew of 6 people. The module contai

UNO [17]

Answer:

294.524 m^3

Explanation:

The volume of a cylinder is given by the formula ...

V = πr^2h

For a radius of 2.5 m and a length of 15 m, the volume is ...

V = π(2.5 m)^2(15 m) = 93.75π m^3 ≈ 294.524 m^3

The volume is about 294.52 cubic meters.

7 0

3 years ago