Two equal resistances R are joined with voltage source V in (i)series (ii)parallel, the ratio of electrical power consumed in two cases will be

• 1:4

• 4:1

• 2:1

• 1:2

When a resistance of α Ω is connected at the ends of a battery, its potential difference decreases from 40 V to 30V. The internal resistance of the battery is

• 3Ω

• 6Ω

• 1.5Ω

• 4Ω

The equivalent resistance and potential difference between A and B for the circuit              

respectively are

• 4Ω, 8V

• 8Ω, 4V

• 2Ω, 2V

• 16Ω, 2V

A wire of resistance R is divided in equal parts, then these parts are joined in parallel, the equivalent resistance of the combination will be

• nR

• $\frac{\mathrm{R}}{\mathrm{n}}$

• $\frac{\mathrm{n}}{\mathrm{R}}$

• $\frac{\mathrm{R}}{{\mathrm{n}}^2}$

The potential difference between point A and B is

• $\frac{20}{7 } \mathrm{V}$

• $\frac{40}{7}\mathrm{V}$

• $\frac{10}{7}\mathrm{V}$

• zero

When a certain current is passed in the circuit as shown in figure, 10 kcal of heat is produced in 5 Ω resistance. How much heat is produced in 4 Ω resistance?

• 4 kcal

• 2 kcal

• 5 kcal

• 3 kcal

In the given circuit, what will be the equivalent resistance between the points A and B ?

• 10 / 3 Ω

• 20 / 3 Ω

• 10 / 5 Ω

• 5 Ω

268.

A uniform wire of length I and having resistance R is cut into n equal parts and all parts are connected in parallel, then the equivalent resistance will be :

• R

• R/n

• R/n²

• n²R

For the network shown in the figure, the value of the current i is

• $\frac{9 \mathrm{V}}{35}$

• $\frac{5 \mathrm{V}}{18}$

• $\frac{5 \mathrm{V}}{9}$

• $\frac{18 \mathrm{V}}{5}$

When a wire of uniform cross-section a, length land resistance R is bent into a complete circle, resistance between two of dimetrically opposite points will be

• $\frac{\mathrm{R}}{4}$

• $\frac{\mathrm{R}}{8}$

• 4R

• $\frac{\mathrm{R}}{2}$