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3 years ago

Calculate the kinetic energy of Julie, a 60 kg biker, traveling at a velocity of 8 m/s to the right

Physics

1 answer:

Vadim26 [7]3 years ago

8 0

Answer:

1,920 Joules

Explanation:

K.E. = 1/2 mv2

so K.E. = 1/2 (60)(8x8) = 1,920 Joules

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vichka [17]

Answer:

e) True, f) False

Explanation:

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$Q_{net,in} - W_{net, out} = \Delta U$ (1)

Where:

$Q_{net, in}$ - Net input heat, measured in joules.

$W_{net, out}$ - Net output work, measured in joules.

$\Delta U$ - Change in thermal energy, measured in joules.

Please notice that work comprises all kind of work (i.e. mechanical, electric, magnetic), whereas heat comprises all heat interactions including chemical and radioactive phenomena.

If thermal energy is released, then $\Delta U < 0$ , which is caused by three scenarios:

(i) $Q_{net,in} < 0$ , $W_{net, out} < 0$ , $|Q_{net,in}|>|W_{net,out}|$

(ii) $Q_{net, in} > 0$ , $W_{net,out} > 0$ , $|Q_{net,in}|$

(iii) $Q_{net,in}< 0$ , $W_{net, out}>0$

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f) A liquid solidifies when temperature goes below point of fusion, meaning a realease of heat with no work interactions. That is:

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Answer:

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Explanation:

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