(i) I1=VR1
(ii) I2=VR2
(iii) I + I1+I2=VR1+VR2
johnmulu answered the question on May 26, 2017 at 07:42
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Figure 1 shows a cell of e.m.f 2 V connected in series with a resistor R and a switch S. Voltmeter V1 and V2 are connected across the cell and the resistor respectively.
(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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Determine the reading of the voltmeter V.
Date posted: May 23, 2017. Answers (1)
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From the graph:
(i) State with a reason whether or not the device obeys ohms law.
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(I) I = 1.5 A
(II) I = 3.5 A
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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
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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.
Date posted: May 23, 2017. Answers (1)
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Figure 6 shows a circuit in which a battery of negligible internal resistance, two resistors a capacitor, a voltmeter and a switch are connected.
Giving a reason for your answer in each case, state the reading of the voltammeter, V, when the switch is (i) Open (ii) Closed
Date posted: May 23, 2017. Answers (1)
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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. Answers (1)
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Calculate the value of the resistance R.
Date posted: May 23, 2017. Answers (1)
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(i) State with a reason whether the device obeys Ohm's law
(ii) Determine the resistance of the device, X when the current through it is 60 mA
Date posted: May 23, 2017. Answers (1)
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Determine the resistance of the conductor.
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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. Answers (1)
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Date posted: May 23, 2017. Answers (1)
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Date posted: May 23, 2017. 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.
Determine:
(i) The current flowing through the 5.5 resistor
(ii) The potential difference between Y and Q.
Date posted: May 23, 2017. Answers (1)
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The bulb is lit. When the thermistor is steadily heated the brightness of the bulb reduces. Explain observation.
Date posted: May 23, 2017. Answers (1)
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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.
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State the:
(i) Velocity ratio of the system.
(ii) Purpose of pulley 2.
(iii) Given that the machine has an efficiency of 80%, determine the maximum load that can be raised.
Date posted: May 16, 2017. Answers (1)