Current Electricity Test

Directions For Questions

A potentiometer is an ideal voltmeter since a voltmeter draws some current through thsadition, a constant current flows throughout the wire of a potentiometer using standard cell of emf $$e_1$$. The wire of potentiometer is made of uniform material and cross-sectional area, and it has uniform resistance per unit length. The potential gradient depends upon the current in the wire.
A potentiometer with a cell of emf 2 V and internal resistance 0.4 $$\omega$$ is used across the wire AB. A standard cadmium cell of emf 1.02 V gives a balance point at 66 cm length of wire. The standard cell is then replaced by a cell of unknown emf e (internal resistance r), and the balance point found similarly turns out to be 88 cm length of the wire. The length of potentiometer wire AB is 1 m.

...view full instructions

Potential difference V (in volt)	0.5	1.0	1.5	2.0	2.5
Current I (in ampere)	0.2	0.4	0.6	0.8	1.0

Current Electri...

Question 1

$$37.5 cm$$

$$3.75 cm$$

$$75 cm$$

$$15 cm$$

Question 2

$$3A$$

$$1A$$

$$-5A$$

$$5A$$

Question 3

$$\displaystyle \frac{2\varepsilon }{n}$$

$$\displaystyle \frac{n -1 }{n}\varepsilon $$

$$\displaystyle \frac{n -2 }{n}\varepsilon $$

$$\displaystyle \frac{2n }{n -2}\varepsilon $$

Question 4

$$3 : 1$$

$$1 : 3$$

$$2 : 3$$

$$3 : 2$$

Question 5

$$V_T< E$$

$$V_T>E$$

$$V_T=0$$

$$V_T=E$$

Question 6

$$1.25 V.$$

$$0.5 V$$

$$2 V$$

$$1 V$$

Question 7

$$\dfrac{Rr}{(R+r)}$$

$$\dfrac{R+r}{2}$$

$$Rr$$

$$R+r$$

Question 8

1.36 V

2.63 V

1.83 V

none

Question 9

0.1 Vcm$$^{-1}$$

0.03 Vcm$$^{-1}$$

0.04 Vcm$$^{-1}$$

0.02 Vcm$$^{-1}$$

Question 10

$$2.5^{\circ}C$$

$$4^{\circ}C$$

$$2^{\circ}C$$

$$1^{\circ}C$$

User

Question Analysis

Results Announcement on: coming Monday

Stay Tuned: We’ll update you on your result via email or SMS.