(i) - Dark fringes are formed as result of destructive interference when a crest of one wave and a trough of another wave arrive at the same point at the same time.
- Bright fringes are formed as a result of constructive interference where crests arrive at the same point at the same time
(ii) There will be no interference pattern because no diffraction takes place.
johnmulu answered the question on May 26, 2017 at 08:41
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In the Young's double slit experiment, and interference pattern of bright and dark fridges was formed as shown in Figure 1 by a light of wavelength coming from two narrow slits X and Y.
(i) Explain how the dark and bright fringes are formed.
(ii) State and explain what would be observed on the screen if the slits X and Y were made large.
Date posted: May 26, 2017. Answers (1)
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Date posted: May 26, 2017. Answers (1)
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State what is observed on the screen when the source is?
(a) monochromatic
(b) white light.
Date posted: May 26, 2017. Answers (1)
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(i) State the function of the double slit.
(ii) Describe what is observed on the screen.
Date posted: May 26, 2017. Answers (1)
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Date posted: May 26, 2017. Answers (1)
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In terms of V1, R1 and R2, write an expression for:
(i) Current I1 through R1
(ii) Current I2 through R2
(iii) Total current I in the circuit.
Date posted: May 26, 2017. Answers (1)
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(a) State the reading of V1 with S open.
(b) With S closed, V1 reads 1.6V. State the reading of V2.
Date posted: May 26, 2017. Answers (1)
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Determine;
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(ii) The resistance of the bulb.
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Figure 3 shows four identical light bulbs connected to a volt battery whose internal resistance is negligible.
Determine the reading of the voltmeter V.
Date posted: May 23, 2017. Answers (1)
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Figure 8, shows a shows a graph of potential difference V (volts) against a current I (amperes) for a certain device.
From the graph:
(i) State with a reason whether or not the device obeys ohms law.
(ii) Determine the resistance of the device at;
(I) I = 1.5 A
(II) I = 3.5 A
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Figure 13, shows a cell in series with a 3 ohms resistor and a switch. A high resistance voltmeter is connected across the cell.
The voltmeter reads 1.5 V with the switch open and 1.2 V with the switch closed
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(ii) Determine the current through the 3 ohm resistor when the switch is closed.
(iii) Determine the internal resistance of the cell
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(a) Explain the change in the shape of the curves as the current increases.
(b) Determine the resistance of the lamps X at the normal working voltage.
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Date posted: May 23, 2017. Answers (1)
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State the value of the circuit through each of the 10 ohm resistors.
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()
Determine:
(i) The e.m.f of the cell.
(ii) The internal resistance of the cell.
(iii) The resistance of the lamp.
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Determine the
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(ii) Current in the circuit
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Date posted: May 23, 2017. Answers (1)
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(i) State with a reason whether the device obeys Ohm's law
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