Class 10 - Science

Electricity Online Mcq Test

Olympiad Level MCQs Also Included

Set-1

1. If the current I through a resistor is increased by 100% (assume that temperature remains unchanged), the increase in power dissipated will be

(a) 100%
(b) 200%
(c) 300%
(d) 400%

2. The resistivity does not change if

(a) the material is changed
(b) the temperature is changed
(c) the shape of the resistor is changed
(d) both material and temperature are changed

3. Electrical resistivity of a given metallic wire depends upon

(a) its length
(b) its thickness
(c) its shape
(d) nature of the material

4. A current of 1 A is drawn by a filament of an electric bulb. Number of electrons passing through a cross-section of the filament in 16 seconds would be roughly

(a) `10^{20}`
(b) `10^{16}`
(c) `10^{18}`
(d) `10^{23}`

5. In an electrical circuit three incandescent bulbs A, B and C of rating 40 W, 60 W and 100 W respectively are connected in parallel to an electric source. Which of the following is likely to happen regarding their brightness?

(a) Brightness of all the bulbs will be the same
(b) Brightness of bulb A will be the maximum
(c) Brightness of bulb B will be more than that of A
(d) Brightness of bulb C will be less than that of B

6. What is the maximum resistance which can be made using five resistors, each of `\frac{1}{5}Ω` ?

(a) `\frac{1}{5}Ω`
(b) 10 Ω
(c) 5 Ω
(d) 1 Ω

7. What is the minimum resistance which can be made using five resistors, each of `\frac{1}{5}Ω`?

(a) `\frac{1}{5}Ω`
(b) `\frac{1}{25}Ω`
(c) `\frac{1}{10}Ω`
(d) 25 Ω

8. An electric kettle consumes 1 kW of electric power when operated at 220 V. A fuse wire of what rating must be used for it?

(a) 1 A
(b) 2 A
(c) 4 A
(d) 5 A

9. Which of the following represents voltage?

(a) `\frac{Work done}{(Current × Time)}`
(b) `Work done × Time`
(c) `\frac{work done × Time}{Current}`
(d) `work done × Current × Time`

10. A cylindrical conductor of length `l` and uniform area of cross-section A has resistance R. Another conductor of length `2l` and resistance R of the same material has an area of cross-section

(a) `\frac{A}{2}`
(b) `\frac{3A}{2}`
(c) 2A
(d) 3A