A toaster operating at 240 V has a resistance of 120 Ω. The power is ______.

(a)

400 W

(b)

2 W

(c)

480 W

(d)

240 W

A carbon resistor of (47 ± 4.7 ) k Ω to be marked with rings of different colours for its identification. The colour code sequence will be ______.

(a)

Yellow – Green – Violet – Gold

(b)

Yellow – Violet – Orange – Silver

(c)

Violet – Yellow – Orange – Silver

(d)

Green – Orange – Violet - Gold

In India electricity is supplied for domestic use at 220 V. It is supplied at 110 V in USA. If the resistance of a 60 W bulb for use in India is R, the resistance of a 60 W bulb for use in USA will be ______.

(a)

R

(b)

2R

(c)

\(\frac{R}{4}\)

(d)

\(\frac{R}{2}\)

In Joule’s heating law, when R and t are constant, if the H is taken along the y axis and I² along the x axis, the graph is ______.

(a)

straight line

(b)

parabola

(c)

circle

(d)

ellipse

Which of the following has negative temperature coefficient of resistance?

(a)

copper

(b)

tungsten

(c)

carbon

(d)

silver

The temperature co-efficient of resistance for alloys is _____________.

(a)

low

(b)

very low

(c)

high

(d)

very high

An electron gun in a TV shoots out a beam of electrons. The beam current is 10\(\mu\)A. The charge that strikes the screen in 1 minute is ______________.

(a)

\(+600\mu C\)

(b)

\(-600\mu C\)

(c)

\(+10\mu C\)

(d)

\(-10\mu C\)

The emf of a battery is 3 volts and internal resistance 0.125 \(\Omega \) . The difference of potential at the terminal of battery when connected across an external resistance of 1 \(\Omega \) is ______________.

(a)

1.67 V

(b)

0.67 V

(c)

2.67 V

(d)

3.67 V

An unknown resistance is connected in parallel with a 15\(\Omega \) resistance and a 12V battery. What is the value of the unknown resistance if the current in the circuit is 2A?

(a)

\(10\Omega \)

(b)

\(20\Omega \)

(c)

\(30\Omega \)

(d)

\(40\Omega \)

Conductor which obey ohm's law are called ______________.

(a)

dielectrics

(b)

superconductors

(c)

ohmic conductors

(d)

semiconductors

An ideal cell is connected to a capacitor through a voltmeter. The reading V of the voltmeter is plotted against time. Which of the following best represents the resulting curve?

(a)

(b)

(c)

(d)

Two identical resistors are connected in parallel then connected in series. The effective resistance are in the ratio ________________.

(a)

1:2

(b)

2:1

(c)

1:4

(d)

4:1

The resistivity of a wire depends on _________________.

(a)

length

(b)

material

(c)

area of cross section

(d)

all the above

Generally the instantaneous current is represented by__________

(a)

i

(b)

I

(c)

dI

(d)

di

When three resistors are connected in series then the value of the effective resistance is _______________.

(a)

less than the individual resistance

(b)

greater than the individual resistance

(c)

greater than or equal to individual resistance

(d)

less than or equal to individual resistance

Electrical Lamp

(1)

ampere

Current

(2)

joule

Resistance

(3)

ohm

Power

(4)

watt

Energy

(5)

Tungsten