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2 years ago

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A 47-kg packing crate is pulled with constant speed across a rough floor with a rope that is at an angle of 37 degrees above the

horizontal. If the tension in the rope is 142 N, how much work is done on the crate to move it 6.1m?

1 answer:

levacccp [35]2 years ago

8 0

Tension in the rope due to applied force will be given as

$F = 142 N$

angle of applied force with horizontal is 37 degree

displacement along the floor = 6.1 m

so here we can use the formula of work done

$W = F d cos\theta$

now we can plug in all values above

$W = 142 * 6.1 * cos37$

$W = 691.8 J$

So here work done to pull is given by 691.8 J

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Answer:

1. $\theta=29.84^{0}$

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For a smaller angle for the first polarizer:

According to Malus Law

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$\sqrt{\frac{163}{327.5} } = sin\theta$

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$\theta=29.84^{0}$

For a larger angle for the first polarizer:

According to Malus Law

$I_{2} =I_{1} cos^{2}\theta$

$\frac{I_{2} }{I_{1} }=Cos^{2}\theta$

taking square root on both sides

$\sqrt{\frac{163}{327.5} } = cos\theta$

$\theta=Cos^{-1}(0.4977)$

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2 years ago

An unknown fluid has a specific gravity of 0.750. What is the volume of 22.5 kg of this fluid?

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<h2>Option C is the correct answer.</h2>

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