Temperature of the water in Fell Beck?

AI Thread Summary
To estimate the temperature change of water in Fell Beck as it falls into Gaping Gill pothole, one can use the specific heat capacity of water (4.2 kJ/(kg*K)) and apply the conservation of energy principle. The gravitational potential energy converted to kinetic energy during the fall can be calculated using the formula for gravitational potential energy. By assuming a mass of 1 kg for simplicity, the energy change can be expressed per unit mass, facilitating the calculation of the temperature change. The discussion emphasizes using specific values to streamline the problem-solving process. This approach will help determine the correct answer from the multiple-choice options provided.
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Hello
I have a question from a multiple choice test and I am not sure what to do with it. It would be great if you could help me :)

Homework Statement



Estimate the change in temperature of the water in Fell Beck before and after it falls into the Gaping Gill pothole (depth 105 m). The specific heat capacity of water is 4.2 kJ/(kg*K).

A) 4 °C
B) 0.25 °C
C) 0.0025 °C
D) 9.2 * 10^-4 °C

Homework Equations



C = m * c

C: Heat capacity
c: Specific heat capacity

Q = C * ΔT

Q: Heat transfer

The Attempt at a Solution



I'm not really sure how to find the mass of the water? Or the energy?
The time I can find (105m = 1/2 * 10m/s^2 * t^2) and the rest I've got the formulas for.

Thank you for the help :)
 
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You can assume a particular quantity of water to work with. 1kg is a nice value :smile: Or you can work with "specific" values, which here means "per unit mass". So for example, the change in energy might be x Joules per kg. This bypasses having to deal with a particular value of mass.

Conservation of energy (gravitational potential energy vs kinetic energy) might be the quickest route to finding your energy due to the fall.
 
Thank you very much :)
 
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