Marc attaches a falling 250-kg object with a rope through a pulley to a paddle wheel shaft. He places the system in a well-insulated tank holding 12 kg of water. When the object falls, it causes the paddle wheel to rotate and churn the water. If the object falls a vertical distance of 100 m at constant speed, what is the temperature change of the water? (1 kcal = 4186 J, the specific heat of
water is 4186 J/kg • °C, and g = 9.8 m/s2)
a. 19,600°C
c. 4.9°C
b. 4700°C
d. 2.3°C
C
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A 40.0 liter gas tank is filled to the brim with gasoline when the temperature is 5.00
Gasoline has a coefficient of volume expansion of 
If the gas tank is moved into the sun of a hot summer day, the temperature of the gas tank is increased to 60.0 
What is the volume of gasoline that overflows the tank (ignore the expansion of the gas tank)?
A. 3.95 liters B. 3.11 liters C. 2.67 liters D. 2.09 liters E. 1.55 liters
The most important advantage of CCDs over film is that:
A) they record much more light in a given exposure time. B) their images do not have to be developed as film does. C) they record colors better than film can. D) they can cover larger areas of the sky than film can. E) their images never fade, as film can.
One positive aspect of the potential use of methane hydrate as a fuel is that
a. there is more of it than there is of coal, oil, and natural gas. b. it is easy to mine. c. its use will never contribute to global warming. d. it exists in a pure form ready for use.
In modern physics, what is heat?
a. A change in energy marked by a change in temperature. b. A change in temperature caused by a change in energy. c. The flow of energy between objects due to a difference in their temperature. d. The opposite of cold. e. A change in work.