Thin Films: When a beam of light that is traveling in air is reflected by a glass surface, there is
A. a 90° phase change in the reflected beam.
B. no phase change in the reflected beam.
C. a 180° phase change in the reflected beam.
D. a 60° phase change in the reflected beam.
E. a 45° phase change in the reflected beam.
Answer: C
You might also like to view...
To investigate the nature of heat produced during the boring process, Count Rumford placed a dull boring tool and a brass cylinder in a barrel filled with cold water. The boring tool was forced against the bottom of the cylinder and rotated by two horses as shown in this figure. What would happen if the water used to cool the bore of the cannon were not replenished while the horses continued to
provide mechanical energy? a. The temperature of the water would decrease as the temperature of the cannon bore increases. b. The temperature of the water would increase until it boils and evaporates. c. It would cause less resistance and the horses will not be able to transmit as much energy though work. d. Only a limited amount of heat can be extracted from the apparatus during a given session, so whether all the water boils away depends on how much water is used. e. Work and heat are distinct, so there is no significant effect on the water.
Thermodynamic Devices: Suppose that the Department of Energy develops a new reversible engine that has a coefficient of performance (COP) of 4.0 when operated as a refrigerator and a COP of 5.0 when operated as a heat pump. What is its thermal efficiency when operated as a heat engine doing work?
A. 10% B. 20% C. 25% D. 45% E. 80%
The first observations of objects in the solar system that orbited neither the sun nor Earth were made by ____________________
Fill in the blank(s) with correct word
Why is atmospheric pressure less on top of a mountain than at sea level?
a. It is cooler in the mountains. b. Denser air sinks to sea level; the air on mountains is lighter. c. The pressure at every height in the atmosphere is due to the weight of the air above it. d. None of the above.