i) Ultra violet light dislodges electrons from the cathode which are attracted by the anode hence the current flows through the circuit.
ii) Increasing the intensity of UV light leads to more electrons being dislodged from the cathode hence more current is recorded by the milliammeter
sharon kalunda answered the question on May 29, 2019 at 13:05
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b) A certain metal has work function of 4.83eV. Calculate the maximum kinetic energy in...(Solved)
The graph below shows the variation of stopping potential against frequency.
From the graph, determine Plank’s constant.
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Date posted: May 29, 2019. Answers (1)
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Calculate :
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ii) charge on the capacitor of 3.2
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Calculate :
i) effective capacitance.
ii) charge on the capacitor of 3.2
iii) p.d across the capacitor of 5
iv) the energy stored by the capacitor of 2
Date posted: May 29, 2019. Answers (1)
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Date posted: May 29, 2019. Answers (1)
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Date posted: May 29, 2019. Answers (1)
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b) Sketch another wave on the same diagram that has double the frequency and...(Solved)
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Date posted: May 29, 2019. Answers (1)
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Explain briefly how it works.
Date posted: May 29, 2019. Answers (1)
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Date posted: May 29, 2019. Answers (1)
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and drew a graph of 1/u against 1/v shown...(Solved)
A student while investigating the focal length of a certain concave mirror, measured object and image distances
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From the graph, determine the focal length.
Date posted: May 29, 2019. Answers (1)
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a) Draw rays of light from the object to the mirror to show...(Solved)
The figure below shows an object O placed infront of a concave mirror.
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b) State one
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ii) application of the set up in (a) above.
Date posted: May 29, 2019. Answers (1)
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State and explain what happens to the leaf when a negative charged rod is brought near...(Solved)
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Date posted: May 29, 2019. Answers (1)
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Date posted: May 29, 2019. Answers (1)
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The maximum wavelength of light required to cause photoelectric emission on a metal surface is 8.0×10-7. The metal surface is irradiated with light of freque4ncy 8.5 × 1014 Hz. Determine
i) The threshold frequency.
ii) The work function of the metal in electron volts.
iii) The maximum kinetic energy of the electron.
iv The maximum velocity of the emitted electrons.
(Take 1ev = 1.6×10-19J, C=3.0×108m/s, h=6.63×10-34Js and mass of electron = 9.11 × 10-31kg)
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Find the power dissipated.(Solved)
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Date posted: May 27, 2019. Answers (1)
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i) Draw a circuit diagram of a reverse biased p-n junction.
ii) From the graph, some...(Solved)
The following diagram represents a reverse bias characteristics of p-n junction.
i) Draw a circuit diagram of a reverse biased p-n junction.
ii) From the graph, some small amount of current flow in the circuit when voltage is zero. Explain.
iii) Current surge is noted at point P in the graph. Explain the cause of this surge.
Date posted: May 27, 2019. Answers (1)
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i) State with a reason whether the device obeys Ohm's law.
ii)...(Solved)
The following graph shows the potential difference, V against current, I for a certain device.
i) State with a reason whether the device obeys Ohm's law.
ii) Determine the resistance of the device when current is 1.5A.
iii) State how resistance of the device varies as current increases from zero to 5.0A.
Date posted: May 27, 2019. Answers (1)
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Date posted: May 27, 2019. Answers (1)
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i) Name the parts labelled A and B.
ii) Explain how change in p.d. across P and Q changes the intensity...(Solved)
Fig below shows an X-ray tube
i) Name the parts labelled A and B.
ii) Explain how change in p.d. across P and Q changes the intensity of x-rays produced.
iii) What property of lead makes it suitable for use as shielding material.
Date posted: May 27, 2019. Answers (1)
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If sensitivity of the Y-gain is 30V/division, find the voltage of the signal.(Solved)
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If sensitivity of the Y-gain is 30V/division, find the voltage of the signal.
Date posted: May 27, 2019. Answers (1)
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Calculate voltage...(Solved)
A transformer has 8000 turns in its primary coil and 200 turns in its secondary coil. The voltage in the primary coil is 240V.
Calculate voltage in the secondary coil.
Date posted: May 27, 2019. Answers (1)