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3 years ago

10

What force does a trampoline have to apply to a gymnast to accelerate her straight up at ? Note that the answer is independent o

f the velocity of the gymnastâshe can be moving either up or down, or be stationary.

1 answer:

Andrew [12]3 years ago

5 0

Answer: Force applied by trampoline = 778.5 N

<em>Note: The question is incomplete.</em>

<em>The complete question is : What force does a trampoline have to apply to a 45.0 kg gymnast to accelerate her straight up at 7.50 m/s^2? note that the answer is independent of the velocity of the gymnast. She can be moving either up or down or be stationary. </em>

Explanation:

The total required the trampoline by the trampoline = net force accelerating the gymnast upwards + force of gravity on her.

= (m * a) + (m * g)

= m ( a + g)

= 45 kg ( 7.50 * 9.80) m/s²

Force applied by trampoline = 778.5 N

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From the question we are told that

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Substituting this into the conservation equation above

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Where $h_c$ is the height where the circular hoop would be released to equal the speed of the sphere at the bottom

$mgh_c = mv^2$

$gh_c = v^2$

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$h_c= \frac{\frac{10gh_s}{7} }{g}$

$= \frac{10h_s}{7}$

Substituting values

$h_c = \frac{10(30)}{7}$

$h_c = 42.86 \ cm$

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