ECAT Pre Computer Science Chapter 12 MCQ Test With Answer

A (100 W , 200 W) bulb is connected to a 160 V power supply. The power consumption would be

• 64 W A
• 80 W B
• 100 W C
• 125 W D

What is the current is a 2 x 10⁶ohm resistor having a potential difference of 2 x 10³volts?

• 10^-1A A
• 10^-2A B
• 10^-4A C
• 1 mA D

An electron of charge e coulomb passes through a potential difference of V volts its energy in joules will be

• V/e A
• eV B
• e/V C
• V D

A certain charge liberates 0.8 g of oxygen. The same charge will liberate. how many g of silver?

• 108 g A
• 10.8 g B
• 0.8 g C
• 108/0.8 g D

• 5μF A
• 10μF B
• 3μF C
• 6μF D

Three resistors of resistance 2,3 and 6 ohms are connected in parallel, their equivalent resistance is

• 11.0 ohm A
• 1.0 ohm B
• 7.0 ohm C
• 3.0 ohm D

Three resistance 500,500 and 50 ohms are connected in series across 555 volts mains. The current flowing through them will be

• 0.52 A A
• 1 mA B
• 0.7 mA C
• 1.4 A D

The speed of randomly moving electrons depends upon

• pressure A
• volume B
• temperature C
• mass D

Cause of heat production in a current carrying conductor is

• Collisions of free electrons with one another A
• High drift speed of free electrons B
• Collisions of free electrons with atoms or ions of conductor C
• High resistance value D

A one microfarad capacitor of a TV is subjected to 4000 V potential difference. The energy stored in capacitor is

• 8 J A
• 16 J B
• 4 x 10^-3J C
• 2 x 10^-3J D

At ordinary temperature, an increase in temperature increases the conductivity of

• Conductor A
• Semiconductor B
• Insulator C
• Alloy D

Which one of the following is the unit of electric field intensity

• JC^-1 A
• Vm^-1 B
• Cm^-1 C
• CJ^-1 D

A capacitor of capacity 1μF is charged to 1 KV. The energy stored in J

• 5 A
• 0.5 B
• 0.005 C
• 50 D

Ohm's law states that

• The current through a resistor is directly proportional to the applied voltage A
• The voltage across a resistor is directly proportional to the current passing through it B
• Resistance is the constant of proportionality between the voltage and current C
• all of these D

If 2.2 kilowatt power is transmitted through 1 10 ohm line at 22000 volt, the power loss in the form of heat will be

• 0.1 watt A
• 1 watt B
• 10 watt C
• 100 watt D