Unit 2 Physics January 2011
Please choose one of the following options for each question:
1. The amount of electrical energy transferred when a charge of 8 mC moves through a potential difference of 12 V is
A. 1500 J
B. 96 J
C. 9.6 x 10
D. 6.7 x 10
2. The battery in the circuit has negligible internal resistance and an e.m.f. of 12 V.
The potential difference across the parallel combination is
A. 0 V
B. 4 V
C. 6 V
D. 8 V
3. A stationary observer hears a sound emitted by a moving source .
This produces a Doppler effect which is a
A. change in frequency of the sound emitted by the source.
B. change in frequency of the sound heard by the observer.
C. change in velocity of the sound emitted by the source.
D. change in velocity of the sound heard by the observer
4. The diagram shows four electron energy levels in an atom. The transition of an electron from level 3 to level 1 is shown. This results in the emission of a photon in the visible range.
Which transition might emit a photon in the ultraviolet range?
A. from level 2 to level 1
B. from level 4 to level 1
C. from level 3 to level 2
D. from level 4 to level 2
5. In the circuit shown, the battery has negligible internal resistance. L, M and N are identical lamps.
The filament of lamp M breaks. Identify the row of the table which shows the resulting changes in the brightness of lamps L and N.
6. Which of the following can be used as a unit of electrical resistance?
A. W A
B. A V
C. W V
D. V C
7. Two waves have the same frequency and are travelling in the same medium.
The two waves can produce a standing wave if they
A. have different amplitudes and travel in opposite directions
B. have different amplitudes and travel in the same direction.
C. have the same amplitude and travel in opposite directions.
D. have the same amplitude and travel in the same direction.
8. The drift velocity v of electrons in a conductor is directly proportional to
A. electron charge.
B. charge carrier density.
C. cross-sectional area.
9. In the 1930s, experiments were performed where beams of X-rays or beams of high energy electrons were directed through a crystal as shown in the diagram.
Which of the following statements about the experiments is correct?
A. They show that the X-rays are behaving like particles.
B. They show that the electrons have a wavelength similar to the size of the atoms.
C. They show that electrons are charged.
D. They show that electrons can have all of the properties of electromagnetic radiation.
10. The graph shows how the current I varies with potential difference V for an electrical component.
Which row of the table gives the resistance of the component at V
and describes how the resistance changes from V