Reference no: EM13613578

1. The water cooling system in a car engine that carries hot water from the engine block to the radiator is an example of cooling by:

• conduction.
• convection.
• radiation.
• transfer.

2. The operation of a simple thermostat depends on:

• the mechanical equivalent of heat.
• specific heat.
• thermal expansion.
• heat of fusion.

3. An ideal gas is heated. If the gas is in a container that prevents its volume from changing, what happens to the pressure?

• It decreases.
• It stays constant.
• It increases.
• This can't be answered without more information.

4. Which of the following is the coldest temperature?

• 356 K
• 201 ºF
• 91 ºC
• 652 ºR

5. Radio waves of wavelength 3 cm have a frequency of:

• 1 MHz.
• 9 MHz.
• 100 MHz.
• 10,000 MHz.

6. J. J. Thompson's measurement of e/m for the electron provides evidence for the:

• wave nature of matter.
• particle nature of matter.
• wave nature of radiation.
• particle nature of radiation.

7. In a photoelectric effect experiment at a frequency above cutoff, the stopping potential is proportional to

• the energy of the least energetic electron before it is ejected.
• the energy of the least energetic electron after it is ejected.
• the energy of the most energetic electron before it is ejected.
• the energy of the most energetic electron after it is ejected.

8. The magnetic field B inside a long ideal solenoid is independent of

• the cross-sectional area of the solenoid.
• the current.
• the core material.
• the spacing of the windings.

9. Helmholtz coils (solenoids) are commonly used in the laboratory (as in the e/m experiment), because the magnetic field between the coils

• can be varied more easily than the fields of other current arrangements.
• is especially strong.
• nearly cancels the earth's magnetic field.
• is nearly uniform.

10. When the speed at which a conductor is moved through a magnetic field is increased, the induced voltage

• stays the same.
• decreases.
• increases.
• depends on the material.

11. When there is current through a wire placed in a magnetic field

• the wire will overheat.
• the wire will become magnetized.
• a force is exerted on the wire.
• the magnetic field will be cancelled.

12. The charge on a glass rod which has been rubbed with silk is called positive

• by established convention.
• so that the proton charge will be positive.
• to conform to the conventions adopted for G and m in Newton's law of gravitation.
• because glass is an insulator.

13. At any point, the magnetic field lines are in the direction of

• the magnetic force on a moving positive charge.
• the magnetic force on a moving negative charge.
• the velocity of a moving negative charge.
• None of the above