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3 years ago

6

If mason runs a 5 k race at an average speed of 300 m/min how long will it take him to finish

1 answer:

makvit [3.9K]3 years ago

6 0

$\\ \sf\Rrightarrow Speed=\dfrac{Distance}{Time}$

$\\ \sf\Rrightarrow Time=\dfrac{Distance}{Speed}$

$\\ \sf\Rrightarrow Time=\dfrac{5000}{300}$

$\\ \sf\Rrightarrow Time=16.6min$

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Answer:

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Or equivalently:

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Since the ball is moving to the left and we assume that the total momentum not changes then the car need to move to the right in order to satisfy the equation and satisfy the balance.

By conservation of the momentum the car will move to the right since the ball is moves to the left.

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A.Yes, and it moves to the right.

Explanation:

If we assume that we have the situation in the figure attached.

For this case we assume that the momentum changes are equal in magnitude and opposite in direction, so then we satisfy this:

$F_c t_ c = -F_b t_b$

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$m_c \Delta V_{c} = -m_b \Delta V_b$

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3 0

3 years ago

An equilibrium is not changed by a change in pressure.<br> a. True<br> b. False

alexandr1967 [171]

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3 years ago

An electron is confined to a one dimensional region, bounded by an infinite potential. If the energy of the electron in its firs

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Answer:

The energy in its ground state is 10 meV.

Explanation:

It is given that,

The energy of the electron in its first excited state is 40 meV.

Energy of the electron in any state is given by :

$E=\dfrac{n^2\pi^2h^2}{8mL^2}$

For ground state, n = 1

$E_1=\dfrac{\pi^2h^2}{8mL^2}$ .............(1)

For first excited state, n = 2

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Dividing equation (1) and (2), we get :

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4 years ago

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3 years ago

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Karolina [17]

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3 years ago