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3 years ago

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From the edge of a roof you throw a snowball downward that strikes the ground with 100J of kinetic energy. then you throw a seco

nd snowball upward with the same initial speed, and this too falls to the ground. neglecting air resistance, the second snowball hits the ground with a kinetic energy of:
a. 100J
b. 200J
c. more than 200J
d. less than 200J
e. none of the above

1 answer:

Vanyuwa [196]3 years ago

7 0

Answer:

The second snowball hits the ground with a kinetic energy of 100 Joules

Explanation:

Given that,

From the edge of a roof you throw a snowball downward that strikes the ground with 100 J of kinetic energy. It is a case of conservation of energy.

At the highest point,

$mgh+\dfrac{1}{2}mu^2=mgh'+0$

$100=mgh'$

At lowest point,

$mgh'=K$

From above two equation, we get :

Kinetic energy, K = 100 J

So, the second snowball hits the ground with a kinetic energy of 100 Joules. So, the correct option is (A).

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2 years ago

Two electrons with a charge of magnitude 1.6×10-19 C in an atom are separated by 1.5×10-10 m, the typical size of an atom. What

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Answer:

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The magnitude of the electric force between two charged particles is given by Coulomb's law:

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where:

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2 years ago

One mol of a perfect, monatomic gas expands reversibly and isothermally at 300 K from a pressure of 10 atm to a pressure of 2 at

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Answer:

Explanation:

Given

1 mole of perfect, monoatomic gas

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3 years ago

A very long straight current-carrying wire produces a magnetic field of 25 µT at a distance d from the wire. How far will the ma

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Given parameters:

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