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2 years ago

How long would it take a 4,560 watt motor to raise a 166 kg piano to an apartment window

Physics

1 answer:

IrinaK [193]2 years ago

8 0

Answer:

Explanation:

We need the power equation here:

P = W/t where W is work and is defined as

W = F*displacement.

Force is a measure in Newtons, which is also weight. We have the mass of the piano, but we need to find the weight:

w = mg so

w = 166(9.8) so

w = 1600N, rounded to the correct number of sig dig. We use that now in the power equation:

$4560=\frac{(1600)(15)}{t}$ and isolating the unknown:

$t=\frac{(1600)(15)}{4560}$ so

t = 5.3 seconds

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Answer:

15.6cm

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2 years ago

To make the next delivery, Sam-I-Am goes 45 mi/h for 2 hours. How far did he travel in that time?

andrezito [222]

Hello =D

This problem is about cinematic

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2 years ago

A block of mass m=1.2 kg is held at rest against a spring with a force constant k=730N/m. Initially the spring is compressed a d

igor_vitrenko [27]

Answer:

Explanation:

potential energy of compressed spring

= 1/2 k d²

= 1/2 x 730 d²

= 365 d²

This energy will be given to block of mass of 1.2 kg in the form of kinetic energy .

Kinetic energy after crossing the rough patch

= 1/2 x 1.2 x 2.3²

= 3.174 J

Loss of energy

= 365 d² - 3.174

This loss is due to negative work done by frictional force

work done by friction = friction force x width of patch

= μmg d , μ = coefficient of friction , m is mass of block , d is width of patch

= .44 x 1.2 x 9.8 x .05

= .2587 J

365 d² - 3.174 = .2587

365 d² = 3.4327

d² = 3.4327 / 365

= .0094

d = .097 m

= 9.7 cm

If friction increases , loss of energy increases . so to achieve same kinetic energy , d will have to be increased so that initial energy increases so compensate increased loss .

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2 years ago

When water in a lake freezes, the ice that forms floats on top of any water that is still liquid. Why does the ice float?

ddd [48]

Answer:

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3 years ago

A single-turn circular loop of wire of radius 45 mm lies in a plane perpendicular to a spatially uniform magnetic field. During

Lina20 [59]

Answer:

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Explanation:

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