(i) I = $\frac{V}{R}$ = $\frac{1.5}{10}$ = 0.15 A
(ii) Voltage across the bulb = 1.5 V
R = $\frac{V}{I}=$\frac{1.5}{0.1}$ = 15 ohms
johnmulu answered the question on May 23, 2017 at 13:43
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Figure 3 shows four identical light bulbs connected to a volt battery whose internal resistance is negligible.
(Solved)
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
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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.
(Solved)
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.
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Date posted:
May 23, 2017
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Answers (1)
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(Solved)
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The voltmeter reads 1.5 V with the switch open and 1.2 V with the switch closed
(i) State the electromotive force of the cell.
(ii) Determine the current through the 3 ohm resistor when the switch is closed.
(iii) Determine the internal resistance of the cell
Date posted:
May 23, 2017
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Answers (1)
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(Solved)
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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
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Answers (1)
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(Solved)
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State the value of the circuit through each of the 10 ohm resistors.
Date posted:
May 23, 2017
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Answers (1)
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(Solved)
In figure 11 the voltmeter reads 2.1 V when the switch is open. When the switch is closed, the voltmeter reads 1.8 V and the ammeter reads 0.1 A.
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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.
Date posted:
May 23, 2017
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Answers (1)
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(Solved)
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Date posted:
May 23, 2017
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Answers (1)
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(Solved)
The cell in Figure 10 has an e.m.f of 2.1 V and negligible internal resistance.
Determine the
(i) Total resistance in the circuit
(ii) Current in the circuit
(iii) Reading of the voltmeter
Date posted:
May 23, 2017
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Answers (1)
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When the device,X is connected in the circuit below, the voltage across it is 0.70 V.
(Solved)
When the device,X is connected in the circuit below, the voltage across it is 0.70 V.
Calculate the value of the resistance R.
Date posted:
May 23, 2017
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Answers (1)
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The graph in Figure 9 shows the current-voltage characteristics of a certain device, X
(Solved)
The graph in Figure 9 shows the current-voltage characteristics of a certain device, X
(i) State with a reason whether the device obeys Ohm's law
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Date posted:
May 23, 2017
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Answers (1)
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(Solved)
The graph below shows the voltage-current relationship for a certain conductor.
Determine the resistance of the conductor.
Date posted:
May 23, 2017
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Answers (1)
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Figure 4 shows an electrical circuit. When the switch is closed the ammeter reading is 0.3 A.
(Solved)
Figure 4 shows an electrical circuit. When the switch is closed the ammeter reading is 0.3 A.
Determine the voltmeter reading.
Date posted:
May 23, 2017
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Answers (1)
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The ammeter in the circuit in Figure 11 has negligible resistance. When the switch S is closed, the ammeter reads 0.10 A. Determine the internal resistance of the battery.
(Solved)
The ammeter in the circuit in Figure 11 has negligible resistance. When the switch S is closed, the ammeter reads 0.10 A. Determine the internal resistance of the battery.
Date posted:
May 23, 2017
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Answers (1)
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The internal resistance of the cell, E in Fig. 3 is 0.5 ohms.
(Solved)
The internal resistance of the cell, E in Fig. 3 is 0.5 ohms.
Determine the ammeter reading when the switch, S is closed.
Date posted:
May 23, 2017
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Answers (1)
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The diagram in Fig. 2 represent an electric circuit in which five resistors are connected to be a battery of e.m.f. 4.0 V and of negligible internal resistance.
(Solved)
The diagram in Fig. 2 represent an electric circuit in which five resistors are connected to be a battery of e.m.f. 4.0 V and of negligible internal resistance.
Determine:
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Date posted:
May 23, 2017
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Answers (1)
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(Solved)
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Date posted:
May 23, 2017
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Answers (1)
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Figure 10 shows a trolley of weight 20 N pulled by a force of 4 N from the bottom to the top of an inclined plane at a uniform speed.
(Solved)
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(i) State the value of the force acting downwards along the inclined plane.
(ii) Explain how the value in part (a)(i) is obtained.
Date posted:
May 16, 2017
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Answers (1)
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(Solved)
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State the:
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Date posted:
May 16, 2017
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Answers (1)
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(Solved)
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Determine the velocity ratio of the jack.
Date posted:
May 16, 2017
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Answers (1)
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(Solved)
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(II) On the mass;
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Date posted:
May 16, 2017
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Answers (1)