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2 years ago

A rock is lying on a rock ledge that is 3 m high. The rock as 120 J of potential energy. What is the mass of the rock?

Physics

1 answer:

Sonja [21]2 years ago

6 0

$\\ \sf\Rrightarrow PE=mgh$

$\\ \sf\Rrightarrow m(10)(3)=120$

$\\ \sf\Rrightarrow 30m=120$

$\\ \sf\Rrightarrow m=4kg$

Mass=4kg

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Assume a satellite shines an unpolarized light on a telescope. The intensity of the light as it reaches the telescope is 1.1*10-

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Answer:

$4.125\times 10^{-11}\ W/m^2$

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4 years ago

A 0.500-kg stone is moving in a vertical circular path attached to a string that is 75.0 cm long. The stone is moving around the

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Answer:

B. 7.07 m/s

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3 years ago

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Read 2 more answers

20 cubic inches of a gas with an absolute pressure of 5 psi is compressed until its pressure reaches 10 psi. What's the new volu

Anna71 [15]

Answer:

B. $V_{f}= 10\,cubic\,inches$

Explanation:

Assuming we are dealing with a perfect gas, we should use the perfect gas equation:

$PV=nRT$

With T the temperature, V the volume, P the pressure, R the perfect gas constant and n the number of mol, we are going to use the subscripts i for the initial state when the gas has 20 cubic inches of volume and absolute pressure of 5 psi, and final state when the gas reaches 10 psi, so we have two equations:

$P_{i}V_{i}=n_{i}RT_{i}$ (1)

$P_{f}V_{f}=n_{f}RT_{f}$ (2)

Assuming the temperature and the number of moles remain constant (number of moles remain constant if we don't have a leak of gas) we should equate equations (1) and (2) because $T_{i}=T_{f}$ , $n_{i}=n_{f}$ and R is an universal constant:

$P_{i}V_{i}= P_{f}V_{f}$ , solving for $V_{f}$

$V_{f} =\frac{P_{i}V_{i}}{P_{f}} =\frac{(5)(20)}{10}$

$V_{f}= 10 cubic\,inches$

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3 years ago