CBSE
Multiple Choice QuestionsA wire of resistance 10Ω is bent to form a complete circle. Find its resistance between two diametrically opposite point.
5 Ω
2.5 Ω
1.25 Ω
Ω
The ammeter shown in figure consists of a 480 Ω coil connected in parallel to a 20 Ω shunt. The reading of ammeter is
0.125 A
1.67 A
0.13 A
0.67 A
When plate voltage in diode valve is increased from 100V to 150V. Then, plate increases from 7.5 mA to 12 mA, then dynamic plate resistance will be
10 kΩ
11 kΩ
15 kΩ
11.1 kΩ
The electron of H - atom is revolving around the nucleus in circular orbit having radius with . The current produced due to the motion of electron is
zero
A copper rod of length 20 cm and cross-sectional area 2 mm is joined with a similar aluminium rod as shown below
The resistance of pair of rods is (ρAl =2.6 x 10-8 Ω-m and ρCu =1.7 x 10-8 Ω-m)
1.0 mΩ
2.0 mΩ
3.0 mΩ
None of these
The galvanometer resistance is 30 Ω and it is connected to 2 V battery along with a resistance 2000 Ω in series. A full scale deflection of 25 divisions is obtained. In order to reduce this deflection to 20 divisions, the resistance in series should be
2470 Ω
2370 Ω
2180 Ω
2210 Ω
Find the resistance of a hollow cylindrical conductor of length 1.0 mm and 2.0 mm respectively. The resistivity of the material is 2.0 × 10-8 Ωm
2.1 × 10-3 Ω
1.3 × 10-4 Ω
3.2 × 10-4 Ω
4.6 × 10-2 Ω
In the given figure, potential difference between A and B is
0 V
5 V
10 V
15 V
A engine pumps up 100 kg of water through a height of 10 m in 5s. Given that, the efficiency of engine is 60%. If g = 10 ms-2, the power of this engine is
3.3 kW
0.33 kW
0.033 kW
33 kW
Find equivalent resistance between X and Y
R
R/L
2R
5R
