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kykrilka [37]
3 years ago
7

Which would be the best example to demonstrate the principle of conservation of energy? A) a stone is crushed B) light bends aro

und a sharp edge C) a pendulum swings back and forth D) a balloon inflates when air is blown into it
Physics
2 answers:
Gnom [1K]3 years ago
7 0

The correct answer to the question is : C) A pendulum swings back and forth.

EXPLANATION:

Before answering this question, first we have to understand the law of conservation of energy.

As per law of conservation of energy, energy can neither be created not be destroyed. It can only change from one form to another form, and the total energy of the universe is always constant.

As per the question, we have a pendulum which is moving back and forth.

Let us consider a pendulum which is taken to some height from its equilibrium or mean point. The energy possessed by the pendulum at this height is gravitational potential energy. When the pendulum is released, the potential energy is converted into kinetic energy. At mean point, whole of its potential energy is converted into kinetic energy.

Due to inertia, the pendulum reaches at the other extreme point. During its movement from mean point to extreme point, the kinetic energy is converted into potential energy. At extreme point, whole of its kinetic energy must have converted into potential energy. The same process will be repeated.

Hence, it obeys law of conservation of energy.

Hence, swinging of pendulum back and forth is the best example to demonstrate the law of conservation of energy.

Daniel [21]3 years ago
6 0
The answer is a pendulum swings back an forth.
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Answer:

a) a=33.73mm/s^{2}

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c) \%_{change}=0.343\%

d) a=24.07mm/s^{2}

Explanation:

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In this case, we know the centripetal acceleration is given by the following formula:

a_{c}=\omega ^{2}r

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\omega=\frac{2\pi}{T}

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T=24hr*\frac{3600s}{1hr}=86400s

so we can now find the angular speed:

\omega=\frac{2\pi}{86400s}

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a_{c} =(72.72x10^{-6} rad/s^{2})^{2}(6478x10^{3}m)

which yields:

a_{c}=33.73mm/s^{2}

b)

In order to answer part b, we must draw a free body diagram of us sitting on a chair. (See attached picture.)

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c)

So let's calculate our weight and normal force:

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and let's calculate the normal force:

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d) In order to find this acceleration, we need to start by calculating the radius of rotation at that point of earth. (See attached picture).

There, we can see that the radius can be found by using the cos function:

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In this case:

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