Disorder in the Universe
In natural processes, the entropy of the universe...
always increases.
How much work is done on a vacuum cleaner pulled 3.0 m by a force of 50 N?
150 J
What is the freezing and boiling point of water in degrees Kelvin?
273 and 373 degrees K
What variable or term has the greatest effect on kinetic energy?
velocity
How much gravitational potential energy is stored in a 15 kg flower pot on a window ledge that is 4 m high?
588 J
The greater the entropy, the _____ energy is available to __________.
less; work
What is the definition and unit of power?
Power is the rate at which work is done. It units are Watts (W).
Temperature measures _____ and _____. It is proportional to the __________ of the atoms or molecules of the substance.
hot and cold; kinetic energy
A substance with high molecular kinetic energy has a ____ temperature.
high
A skater has 30 J of potential energy and 30 J of kinetic energy midway down a skate ramp. How much mechanical energy does the skater have?
60 J
What is internal energy? What are its units?
Internal energy is the total energy of the particles. The unit of internal energy is the Joule (J).
A waitress carries a 1.5 kg platter of food 2 m above the ground at a constant velocity. How much work is being done on the platter?
0 J
When two bodies that are in physical contact have identical temperatures, this is called __________. Is energy exchanged in this situation?
thermal equilibrium, no energy is exchanged
A spring with a force constant of 5.2 N/m has a relaxed length of 2.45 m. When a mass is attached to the end of the spring it stretches the spring to a length of 3.57 m. What is the elastic potential energy stored in the spring?
3.26 J
A spring is compressed 0.25 m from its relaxed state. The spring holds 12 J of elastic potential energy. What is the spring constant?
384 N/m
If you mix 100 mL of 90 degree C hot water with 100 mL of cold 10 degree C water, what is the final temperature of the mixture?
50 degree C
To do work on an object, the force acting on the object must _____ the displacement of the object.
cause
For heat to be transferred between objects there must be a difference in _________.
temperature
A dog pulls a sled with a force of 4 N for 7m. If it takes 22 seconds to pull the sled this distance, how much power is exerted by the dog?
1.27 W
A ball is pushed from rest with a constant force of 16 N. How far must the ball be pushed so that its final kinetic energy is 400 Kg?
25 m
That the total entropy of any isolated system increases is which law of thermodynamics?
2nd Law of Thermodynamics
A 100 kg student climbs three flights of stairs that total 20 m high in 30 seconds. What is the power generated by the student?
653 W
A substance that heats up slowly has a ____ specific heat capacity.
high
Which has the greatest internal energy: a cold swimming pool or a hot cup of coffee?
a cold swimming pool
A 1.5 kg apple falls from a tree. The apple falls 3 m to the ground. What is the kinetic energy of the apple when it hits the ground? What is the velocity of the apple the instant it hits the ground?
44.1 J; 7.7m/s