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3 years ago

If a force does a positive amount of work on an object, does the object's speed

Physics

1 answer:

Alexxandr [17]3 years ago

8 0

The speed of the object increases

Explanation:

We can answer this question by applying the work-energy theorem, which states that the work done on an object is equal to the change in kinetic energy of the object. Mathematically:

$W=K_f -K_i= \frac{1}{2}mv^2-\frac{1}{2}mu^2$

where

W is the work done on the object

$K_f, K_i$ are the final and initial kinetic energy of the object, respectively

m is the mass of the object

v is its final speed

u is its initial speed

In this case, the force does a positive amount of work on the object, so

$W>0$

This also implies that

$K_f > K_i$

And so

$\frac{1}{2}mv^2 > \frac{1}{2}mu^2$

And therefore

$v>u$

which means that the speed of the object increases.

Learn more about work:

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3 years ago

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Kitty [74]

Answer:

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Explanation:

Given that,

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We need to calculate the minimum width

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$D\sin\theta=n\lambda$

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