Question

1. If you have the same mass of water in a bathtub at the same initial temperature your hot bath will last ______ if you were somehow able to increase the specific heat of the water?

a. a shorter time

b. a longer time

c. the same time

2. The Ehrenfest Dog/Flea problem is most similar to the following experiment or problem:

a. a phase change problem

b. a calorimeter problem

c. a Bernoulli's principle problem

d. a specific heat problem

3. In polar areas we have ice floating on water and ice on land. Which of those will raise the sea level by melting?

a. both

b. floating ice melting will raise the sea level, land ice melting will not

c. floating ice melting will not raise the sea level, land ice melting will

d. neither

6. A hydraulic lift has a small cylinder with an area of 0.010 m². The large cylinder of the lift has an area of 1,000 m². If we put a weight of 100 Newtons on the cap of the small cylinger what is the upward force in the large cylinder?

a. 10,000 N

b. 100,000 N

c. One million N

d. ten million N

e 100 million N

Answer 1

1) Note that more the specific heat, more is the energy needed to change the temperature,

therefore,

If you have the same mass of water in a bathtub at the same initial temperature your hot bath will last A LONGER TIME if you were somehow able to increase the specific heat of the water.

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2) I am not sure about this but I think it should be phase change

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3) In polar areas we have ice floating on water and ice on land. Which of those will raise the sea level by melting

Answer - floating ice melting will not raise the sea level, land ice melting will

Reason - Floating ice is already in the sea , so it will displace the same volume after it melts as it did before melting. However, melting of ice on land will add more water

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6)

assuming the pressure is same in small and large cylinders

P1 = P1

F1 / A1 = F2 / A2

where 1 is for large and 2 is for small cylinder

so,

F1 / 1000 = 100 / 0.01

F1 = 10 million Newtons