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14 days ago

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3.113 A heat pump is under consideration for heating a research station located on Antarctica ice shelf. The interior of the sta

tion is to be kept at 15℃. Determine the maximum theoretical rate of heating provided by a heat pump, in ????W p???????? ????W of power input in each of two cases: The role of the cold reservoir is played by (a) the atmosphere at −20℃, (b) ocean water at 5℃.

1 answer:

ValentinkaMS [2.4K]14 days ago

6 0

Answer:

a. β = 8.23 K

b. β = 28.815 K

Explanation:

The performance of the heat pump can be calculated using the formula

β = TH / (TH - TC)

a.

TH = 15 ° C + 273.15 K = 288.15 K

TC = - 20 ° C + 273.15 K = 253.15 K

β = 288.15 K / (288.15 K - 253.15 K)

β = 8.23 K

b.

TH = 15 ° C + 273.15 K = 288.15 K

TC = 5 ° C + 273.15 K = 278.15 K

β = 288.15 K / (288.15 K - 278.15 K)

β = 28.815 K

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Answer:

The resulting velocity for him will be 0.187 m/s in reverse direction.

Explanation:

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The final velocity of the ball is, $v_b=3.50\ m/s$

The final velocity of the man is, $v_m=?\ m/s$

To determine this scenario, we employ the principle of momentum conservation.

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Momentum is calculated by multiplying mass by velocity.

Initial momentum = Initial momentum of the man and the ball

Initial momentum = $Mu_m+mu_b=75\times 0+4\times 0 =0\ Nm$

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The negative sign indicates that the man moves backward.

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1 month ago

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Right after this, the arrow produces a muffled noise, traveling the same distance d at a speed of 340 m/s in time $t_{sound}$ . Thus, we can derive:

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Using this relationship in the distance formula for sound allows us to write:

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Now, after some calculations, we can proceed further:

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