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3 years ago

10

a 70 kg desk sits on the floor motionless If gravity is pulling it with an acceleration of 9.8 m/s/s how much force is gravity e

xercising on the desk

1 answer:

adell [148]3 years ago

3 0

Since force is mass*acceleration,

F = 70kg * 9.8 m/s

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gregori [183]

Answer:

1. Torque → F. Study of forces

2. C.O.G → D. Point of action of weight.

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3 years ago

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Lisa [10]

Answer:

t = 4.0 min

Explanation:

given data:

diameter of rod = 2 cm

T_1 = 100 degree celcius

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WE KNOW THAT

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$Lc = \frac{V}{A_s}$

$Lc = \frac{\frac{\pi D^2}{4} L}{\pi DL}$

$Lc = \frac{D}{4}$

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Bi = 0.0025

As Bi is greater than 0.1 therefore lumped system analysis is applicable

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b = 0.01163 s^{-1}

putting value in equation 1

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solving for t we get

t = 4.0 min

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$75kg*m/s = 5.0kg*v$

$v=\dfrac{75}{5}$

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The core of a star must be at the temperature of 10,000,000 degrees Celsius for hydrogen fusion to begin.

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