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drek231 [11]
3 years ago
6

A(n) 930 N crate is being pushed across a level floor by a force of 400 N at an angle of 20◦ above the horizontal. The coefficie

nt of kinetic friction between the crate and the floor is 0.20. The acceleration of gravity is 9.81 m/s 2 . What is the magnitude of the acceleration of the box? Answer in units of m/s 2

Physics
1 answer:
Nana76 [90]3 years ago
3 0

Answer:

The magnitude of the acceleration of the box is 2.291\,\frac{m}{s^{2}}.

Explanation:

The free body diagram of the crate is included as attachment, whose equations of equilibrium are described below:

\Sigma F_{x} = P\cdot \cos 20^{\circ} - \mu_{k}\cdot N = \left(\frac{W}{g}\right)\cdot a

\Sigma F_{y} = P\cdot \sin 20^{\circ} + N - W = 0

From second equation of equilibrium we find an expression for the normal force and find the respective value:

N = W - P \cdot \sin 20^{\circ}

N = 930\,N - 400\cdot \sin 20^{\circ}\,N

N = 793.192\,N

Lastly, the acceleration experimented by the crate during pushing is cleared in the first equation of equilibrium and consequently calculated:

a = \frac{P\cdot \cos 20^{\circ}-\mu_{k}\cdot N}{\frac{W}{g} }

a = \frac{400\cdot \cos 20^{\circ}\,N-0.20\cdot (793.192\,N)}{\frac{930\,N}{9.807\,\frac{m}{s^{2}} } }

a = 2.291\,\frac{m}{s^{2}}

The magnitude of the acceleration of the box is 2.291\,\frac{m}{s^{2}}.

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An astronaut is rotated in a horizontal centrifuge at a radius of 5.0 m. (a) What is the astronaut’s speed if the centripetal ac
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A diode, which allows current to flow in one direction only, consists of two types of semiconductors joined together.

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