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3 years ago

If a pulley with six supporting ropes is used to lift a 1200 lb piano, what input force is needed?

Physics

2 answers:

Vladimir [108]3 years ago

5 0

Answer:

D) 200 Lb

Explanation:

As we know that the piano is balanced by six ropes connected to it

by the force balance we can say that tension force of all ropes will combined to balance the weight of the object

So here we can say by force equation we will have

$6T = mg$

so we will have

$T = \frac{mg}{6}$

here we know that

$mg = 1200 lb$

so we will have

$T = \frac{1200}{6} = 200 lb$

Lisa [10]3 years ago

3 0

The correct answer is d) 200 lbs.

Hope that I was of help.

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olya-2409 [2.1K]

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Explanation:

Given

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3 years ago

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alexdok [17]

Answer:

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Explanation:

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Using,

Vs/Vp = Ns/Np.......................... Equation 1

Where Vs = Voltage in the secondary coil, Vp = Voltage in the primary coil, Ns = number of turn in the secondary coil, Np = number of turns in the primary coil.

Make Vs the subject of the equation

Vs = Vp(Ns/Np)........................ Equation 2

Given: Vp = 120 v, Np = 1000 turns, Ns = 100 turns

Substitute into equation 2

Vs = 120(100/1000)

Vs = 120×0.1

Vs = 12 v

For the current,

Using

Ns/Np = Ip/Is....................... Equation 3

Where Ip = current in the primary coil, Is = current in the secondary coil

make Is the subject of the equation

Is = Ip(Np/Ns).................. Equation 4

Given: Np = 1000 turns, Ns = 100 turns, Ip = 0.05 A

Substitute into equation 4

Is = 0.05(1000/100)

Is = 0.05×10

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3 years ago

Read 2 more answers

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lawyer [7]

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3 years ago

Refrigerant-134a enters an adiabatic compressor as saturated vapor at -24C and leaves at 0.8 MPa and 60C. When the mass flow r

sergey [27]

Answer:

= 287kW

Explanation:

Knowing the enthalpy data, we have to

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3 years ago

The drawings show two examples in which a ray of light is refracted at the interface between two liquids. In each example the in

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Answer:

Possible options:

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Explanation:

When the light is refracted into liquid B it is bent away from the normal, so that nA > nB. When the light is refracted into liquid C it is bent toward the normal, so that nC > nA. Therefore, we conclude that nC > nA > nB

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3 years ago