Problem 1
A mass of \(1.4 \mathrm{kg}\) of water at \(22^{\circ} \mathrm{C}\) is poured from
a height of \(2.5 \mathrm{m}\) into a vessel containing \(5.0 \mathrm{kg}\) of
water at \(22^{\circ} \mathrm{C} .\) (a) How much does the internal energy of
the \(6.4 \mathrm{kg}\) of water increase? (b) Is it likely that the water
temperature increases? Explain.
Problem 2
The water passing over Victoria Falls, located along the Zambezi River on the border of Zimbabwe and Zambia, drops about \(105 \mathrm{m} .\) How much internal energy is produced per kilogram as a result of the fall?
Problem 3
How much internal energy is generated when a \(20.0-\mathrm{g}\) lead bullet, traveling at \(7.00 \times 10^{2} \mathrm{m} / \mathrm{s},\) comes to a stop as it strikes a metal plate?
Problem 5
A child of mass \(15 \mathrm{kg}\) climbs to the top of a slide that is $1.7
\mathrm{m}\( above a horizontal run that extends for \)0.50 \mathrm{m}$ at the
base of the slide. After sliding down, the child comes to rest just before
reaching the very end of the horizontal portion of the slide. (a) How much
internal energy was generated during this process? (b) Where did the generated
energy go? (To the slide, to the child, to the air, or to all three?)
Problem 6
A 64 -kg sky diver jumped out of an airplane at an altitude of $0.90
\mathrm{km} .$ She opened her parachute after a while and eventually landed on
the ground with a speed of \(5.8 \mathrm{m} / \mathrm{s} .\) How much energy was
dissipated by air resistance during the jump?
Problem 7
During basketball practice Shane made a jump shot, releasing a
\(0.60-\mathrm{kg}\) basketball from his hands at a height of \(2.0 \mathrm{m}\)
above the floor with a speed of \(7.6 \mathrm{m} / \mathrm{s}\) The ball
swooshes through the net at a height of \(3.0 \mathrm{m}\) above the floor and
with a speed of \(4.5 \mathrm{m} / \mathrm{s}\). How much energy was dissipated
by air drag from the time the ball left Shane's hands until it went through
the net?
Problem 8
An experiment is conducted with a basic Joule apparatus, where a mass is
allowed to descend by \(1.25 \mathrm{m}\) and rotate paddles within an insulated
container of water. There are several different sizes of descending masses to
choose among. If the investigator wishes to deliver \(1.00 \mathrm{kJ}\) to the
water within the insulated container after 30.0 descents, what descending mass
value should be used?
Problem 9
Convert \(1.00 \mathrm{kJ}\) to kilowatt-hours \((\mathrm{kWh})\).
Problem 12
If \(125.6 \mathrm{kJ}\) of heat are supplied to \(5.00 \times 10^{2} \mathrm{g}\)
of water at \(22^{\circ} \mathrm{C},\) what is the final temperature of the
water?
Problem 13
It is a damp, chilly day in a New England seacoast town suffering from a power
failure. To warm up the cold, clammy sheets, Jen decides to fill hot water
bottles to tuck between the sheets at the foot of the beds. If she wishes to
heat \(2.0 \mathrm{L}\) of water on the wood stove from $20.0^{\circ}
\mathrm{C}\( to \)80.0^{\circ} \mathrm{C},$ how much heat must flow into the
water?
