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3 years ago

8

A crate of books rests on a level floor. To move it along the floor at a constant velocity, why do you exert less force if you p

ull it at an angle Ï above the horizontal than if you push it at the same angle below the horizontal?

1 answer:

Mademuasel [1]3 years ago

8 0

Answer:should be a matter of vector analysis.

Pulling above the horizontal has less surface area for the opposing friction

Explanation:

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Answer:

c) 3176 J

Explanation:

mass of 125 popcorn = 125 x .0001 = . 0125 kg

increase in temperature = 175 - 21 = 154°C

specific heat of popcorn = 1650

heat required to increase temperature

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= .0125 x 154 x 1650

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Answer:

5. 9GmM/(10R)

Explanation:

m is the mass of the satellite

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W = Energy at earth surface - Potential energy (PE)

But PE = $-\frac{GMm}{R}$

Therefore: W = Energy at earth surface - $\frac{GMm}{R}$

Energy at earth surface (E) at an altitude of 5R = $-\frac{GMm}{5r} +\frac{1}{2}mV^2$

But $V=\sqrt{\frac{GM}{5R} }$

Therefore: $E=-\frac{GMm}{5R}+\frac{1}{2}m(\sqrt{\frac{GM}{5R} } )^2= -\frac{GMm}{5R}+\frac{GMm}{10R} = -\frac{GMm}{10R}$

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Help mee! Physics i think!

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Answer:

Use the form of equation:

Q=mL

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Answer:

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