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iv. When you use a hand pump to inflate the tires of your bicycle, the pump gets warm after a while. Why? What happens to the temperature of the air in the pump as you compress it? Why does this happen? When you raise the pump handle to draw outside air into the pump, what happens to the temperature of the air taken in? Again, why does this happen?reason

User Rue Vitale
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Final answer:

When you use a hand pump to inflate the tires of your bicycle, the pump gets warm after a while because compressing the air increases its temperature. The temperature of the air taken in when the pump handle is raised remains constant.

Step-by-step explanation:

When you use a hand pump to inflate the tires of your bicycle, the pump gets warm after a while because the act of compressing the air causes an increase in temperature. When you compress the air in the pump, you are doing work on the gas, which increases its internal energy and therefore its temperature. When you raise the pump handle to draw outside air into the pump, the temperature of the air taken in remains roughly constant since it is not being compressed.

User Dbn
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Answer:

The temperature rises because for a given volume of gas, a rise pressure of the gas in pressure results in a proportionate rise in the temperature of the gas

Similarly when the handle is raised to draw air causes a fall in pressure that results in proportionate fall in temperature, for a given volume of gas

Step-by-step explanation:

From Gay-Lussac's law, states that the pressure of a given mass of gas is directly proportional to its Kelvin temperature, provided that the volume is held constant

Mathematically, the law states that Pressure ∝ Temperature, at constant Volume

Therefore;

P₁/T₁ = P₂/T₂

Similarly, by kinetic theory of gases, we have;

The


P = (n \cdot MW \cdot v_(rms)^2)/(3 \cdot V)


v_(rms) = \sqrt{(3 \cdot R \cdot T)/(MW) }

Therefore, as in order for the hand pump to inflate the bicycle tires, the air in the pump has to be compressed to force it into the tire, thereby increasing the pressure, of the air in a given volume of the pump which results in the raising of the temperature of the air in the pump, which raises the temperature of the wall of the pump.

The temperature of the air in the pump also falls as the pressure in the pump is reduced by raising the pump handle, to reduce the air pressure inside the pump and and allow air to be taken into the pump.

User John R Smith
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