CBSE
Multiple Choice QuestionsAssertion: In a simple battery circuit, the point of the lowest potential is positive terminal of the battery.
Reason: The current flows towards the point of the higher potential, as it does in such a circuit from the negative to the positive terminal.
If both the assertion and reason are true and reason is a correct explanation of the assertion.
If both the assertion and reason are true and reason is not a correct explanation of the assertion.
If the assertion is true but the reason is false.
If both assertion and reason are false.
If there is no deflection in the galvanometer connected in a circuit shown in the figure, then the ratio of lengths AC/CB is
4:1
1:4
1:1
2:1
An electric bulb marked 40 W and 200 V, is used in a circuit of supply voltage 100 V. Now its power is
100 W
20 W
40 W
10 W
Dimension of resistivity is
[ M L2 T-2 A-1 ]
[ M L3 T-3 A-2 ]
[ M L3 T-2 A-1 ]
[ M L2 T-2 A-2 ]
A current of 6 A enters one comer P of an equilateral triangle PQR having 3 wires of resistances 2Q each and leaves by the corner R. Then the current I1 and I2 are
2 A, 4 A
4 A, 2 A
1 A, 2 A
2 A, 3 A
A potentiometer having the potential gradient of 2 mV/cm is used to measure the difference of potential across a resistance of 10Ω. If a length of 50 cm of the potentiometer wire is required to get the null points the current passing through the 10Ω resistor is (in mA)
1
2
5
10
When a wire is stretched and its radius becomes r/2, then its resistance will be
16 R
2R
4R
0
A battery consists of a variable number (n) of identical cells, each having an internal resistance r connected in series. The terminals of the battery are short-circuited. A graph of current (I) in the circuit versus the number of cells will be as shown in figure
A potentiometer has a uniform potential gradient across it. Two cells connected in series (i).to support each other and (ii).to oppose each other, are balanced over 6m and 2m, respectively on the potentiometer wire. The emf's of the cells are in the ratio of
1 : 2
1 : 1
3 : 1
2 : 1
A battery of emf 10 V and internal resistance 3 Ω is connected to a resistor. The current in the circuit is 0.5 A. The terminal voltage of the battery when the circuit is closed is
10 V
zero
1.5 V
8.5 V
