Need help Little Confused!

  • Thread starter DevilDoc
  • Start date
Just confused :confused: with the questions. I can't find the answer anywere.

The moderate temperatures of islands through out the world has much to do with water's? I'm thinking high specific heat or reflection of solar radiation but not sure.

Dr Transport

Science Advisor
Gold Member
Specific heat is the answer, the oceans absorb the energy from the sun and do not cool down very quickly.
Additional help.

I'm not really good in math. Please help, not sure If got the right answer.

1 ) 2000 grams of water absorbs 5000 J of heat. If the specific heat of water is 1 cal/g C. What is the change of temperature of the water?
My answer is: 0.595 C.

2) When a tiger drinks water, it ames portion of water oscillating up and down four complete cycles per second. As the water wave spreds, the wavelength is 5 CM. What is the wave's speed?
My answer is: 1.25 m/s.
I agree with the temperature change--actually, I got 0.597 degrees using 4.186 Joules = 1 calorie.

For the speed, are you using wavelength*frequency = speed ? Notice that the wavelength is in centimeters; I got 0.2 m/s.

Another question: do circular wavefronts on the water's surface maintain equal spacing as they spread out? The tiger's tongue is oscillating at a constant rate--so a bob placed any distance from the center would bob up and down at a constant (temporal) rate--but do the ripple peaks get closer together or further apart as you go out? I'm just wondering if it's really fair to talk about the 'wavelength' for such a mode of propagation.


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