Q2 of 9 Page 138

The figure shows a conductor of resistance 8 Ω connected in a circuit in the circular shape.


Of these, which gives minimum resistance? Justify your answer.

The second diagram gives minimum resistance as the resistance is directly proportional to length; in the second diagram the electrons have to travel through less resistance as the distance between A and B is less.


More from this chapter

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5

A potential difference of 6 V is applied across a conductor having 12 Ω resistance. How much current will pass through it?

How many times will the current increase if length of the resistor is halved and potential difference is doubled?

 6

What mode of connection of three resistors of 3 Ω each will produce minimum resistance? What will produce maximum resistance? Draw the diagram and calculate the effective resistance.

 1

Draw the method of connecting four resistors of 2 Ω each to get .

 3

Construct a pencil rheostat as shown in the figure. Arrange a science corner to exhibit a model using this to show the factors affecting the resistance of a conductor and to explain Ohm’s Law.


Make a channel on the sole of a slipper so as to place three cells. Remove the wooden insulation from half the pencil length wise so that the graphite can be seen. Fix a bulb holder and the pencil on the sole using glue. Then arrange clips, safety pin, cells and bulb as shown in the figure.