Q. 83.8( 86 Votes )
Fill in the blanks:
a. Longer line in the symbol for a cell represents its ________terminal.
b. The combination of two or more cells is called a ______.
c. When current is switched ‘on’ in a room heater, it ___________.
d. The safety device based on the heating effect of electric current is called a _________.
a. Longer line in the symbol for a cell represents its positive terminal. A battery has two ends. The longer line represents positive end and the shorter line represents negative end.
b. The combination of two or more cells is called a battery. When two or more cells are combined together, they are known as battery.
c. When current is switched ‘on’ in a room heater, it gets heated. This happens because of heating effects of current.
d. The safety device based on the heating effects of electric current is called a fuse. Using an electric fuse prevents the flow of unduly high electric current and protects the appliances from the damage.
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Zubeda made an electric circuit using a cell holder shown in Fig. 14.4, a switch and a bulb. When she put the switch in the ‘ON’ position, the bulb did not glow. Help Zubeda in identifying the possible defects in the circuit.NCERT Science
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identify the problem? Make necessary changes in the circuit to make
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When a switch is in OFF position,
(i) circuit starting from the positive terminal of the cell stops at the switch.
(ii) the circuit is open.
(iii) no current flows through it.
(iv) current flows after some time.
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Paheli took a wire of length 10 cm. Boojho took a wire of 5 cm of the same material and thickness. Both of them connected the wires as shown in the circuit given in Figure 14.4. The current flowing in both the circuits is the same.
(i) Will the heat produced in both the cases be equal? Explain.
(ii) Will the heat produce be the same if the wires taken by them are of equal lengths but of different thickness? Explain.
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