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3 years ago

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A student has a mass (including clothes and shoes) of 65.0 kg. She drinks a 12 oz. can of soda, with a nutritional energy conten

t of 140 Cal. Assuming that the efficiency of her muscles is 20%, how high can she climb without losing weight?
Conversion: 1 Cal = 1,000 cal = 4,180 J

1 answer:

Vikentia [17]3 years ago

4 0

She can climb 0.92 m without losing weight.

<u>Explanation:</u>

Gravitational potential energy is the energy consisting of the product of mass, gravity and height.

1 cal = 4184 J

140 cal = 585760 J

Energy = 585760 J, m = 65.0 kg = 65000 g, Efficiency = 20 %

GPE = mgh

where m represents the mass

g represents the gravity,

h represents the height.

585760 = 65000 9.8 h

h = 0.92 m.

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Answer:

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Explanation:

Given that,

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$\dfrac{dE}{dt}(\pi r^2)=\dfrac{d\phi_{E}}{dt}$

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$\oint{\vec{B}\cdot \vec{ds}}=\mu_{0}(I+\epsilon_{0}\dfrac{d\phi_{E}}{dt})$

$\oint{\vec{B}\cdot\vec{ds}}=\mu_{0}I+\mu_{0}\epsilon_{0}\dfrac{d\phi_{E}}{dt})$

Electric field is zero inside the circle.

$\oint{\vec{B}\cdot \vec{ds}}=\mu_{0}\epsilon_{0}\dfrac{d\phi_{E}}{dt})$

$B(2\pi\times10.0\times10^{-2})=4\pi\times10^{-7}\times8.85\times10^{-12}\times0.0503$

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The electric field produced by a single point charge is given by:

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