(i) A -electron beam
B - copper Anode
(ii) When potential across PQ is increased, the temperature of the cathode increases. This increases the number of electrons released hence the intensity of X - rays
(iii) Most of the Kinetic energy is lost to heat.
(iv) It has very high density.
johnmulu answered the question on June 6, 2017 at 05:48
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Figure 10 shows the waveform of a signal applied at the y - plates of an oscilloscope whose time-base is switched to the scale of 2 milliseconds per centimeter.
Determine:
(i) The period of the signal;
(ii) The frequency of the signal.
Date posted: June 6, 2017. Answers (1)
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Figure 9 shows a cathode ray tube in which a beam of electrons is cast on the screen.
(i) State how electrons are produced in the tube.
(ii) state how electron beam is detected.
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Date posted: June 6, 2017. Answers (1)
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Figure 10 shows the main features of a cathode ray oscilloscope (CRO).
(i) Name the part labeled M and N.
(ii) Explain how electrons are produced in the tube.
(iii) State why the tube is highly evacuated.
Date posted: June 6, 2017. Answers (1)
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Figure 14 (a) is a diagram of a cathode ray tube. M and N are parallel vertical plates.
When switch S is open, a spot is seen at the centre of the screen as shown in Figure 14
(i) State what happens to the sport when S is closed.
(ii) State what would happen to the spot if the potential difference across MN is increased
Date posted: June 6, 2017. Answers (1)
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Figure 14 shows the features of a cathode ray tube.
(i) Name the parts labeled A and B.
(ii) Explain how the electrons are produced in the tube.
(iii) State two functions of the anodes.
(iv) At what part of the cathode ray tube would the time be connected?
(v) Why is a vacuum created in the tube?
Date posted: June 5, 2017. Answers (1)
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What property of the beam of electrons shows that the electrons are traveling at a very high speed?
Date posted: June 5, 2017. Answers (1)
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Figure 3 shows the main features of a cathode ray tube (CRT) of a cathode ray oscilloscope (CRO).
(i) Describe how the electrons are produced in the tube.
(ii) State and explain the function of the grid.
(iii) State what would be observed on the screen if an a.c voltage is connected across the y-plates.
Date posted: June 5, 2017. Answers (1)
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Figure 12 shows a section of a house wiring system.
(i) Name:
the circuit labeled P.
the terminals labeled X and Y.
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Date posted: June 5, 2017. Answers (1)
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Date posted: June 5, 2017. Answers (1)
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Figure 15, shows two coils A and B placed close to each other. A is connected to a steady D.C. Supply and a switch, B is connected to a sensitive galvanometer.
(i) The switch is now closed. State the observations made on the galvanometer.
(ii) Explain what would be observed if the switch is then open.
Date posted: June 5, 2017. Answers (1)
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Date posted: June 5, 2017. Answers (1)
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Figure 5 shows a magnet being moved towards a stationary solenoid. It is observed that a current flows through the circuit in a direction Q to P.
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Date posted: June 5, 2017. Answers (1)
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Figure 12 shows two circuits close to each other.
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Date posted: June 5, 2017. Answers (1)
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Date posted: June 5, 2017. Answers (1)
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Name the parts labeled P and Q
Date posted: June 5, 2017. Answers (1)
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Date posted: June 5, 2017. Answers (1)
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(a) State and explain what would be observed on the galvanometer immediately the switch S is closed.
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Date posted: June 5, 2017. Answers (1)
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Date posted: June 5, 2017. Answers (1)