Define the unit of current.

2

(a)

Calculate the number of electrons constituting one coulomb of charge.

2

(a)

Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?

2

(a)

An electric lamp of 100 \(\Omega \), a toaster of 50 \(\Omega \), and a water filter of resistance 500 \(\Omega \) are connected in parallel to a 220 V source. What is the resistance of an electric iron connected to the same source that takes as much current as all the three appliances, and what is the current through it?

2

(a)

An electric motor takes 5 A from a 220 V line. Determine the power of the motor and energy consumed in 2 h.

2

(a)

An electric heater is used on 220 V supply and takes a current of 3.4 A. Calculate (i) its power and (ii) its power and (ii) its resistance when it is in use.

2

(a)

An electric lamp is marked 100 W, 220 V. It i used for 5 hours daily. Calculate.
(i) its reistance while glowing
(ii) energy consumed in kWh per day

2

(a)

A bulb is rated at 5.0 volt, 100 mA. Calculate its
(i) power and
(ii) resistance

2

(a)

Why is the current constant in series connection of circuit?

2

(a)

How does use  of a fuse wire protect electric appliances?

2

(a)

How is a voltmeter connected in the circuit to measure the potential difference between two points?

2

(a)

Which uses more energy, a 250 W TV set in 1 h or a 1200 W toaster in 10 min?

2

(a)

An electric heater of resistance 8 \(\Omega\) draws 15 A from the service mains 2 hours. Calculate the rate at which heat is developed in the heater.

2

(a)

Draw a circuit diagram of an electric circuit containing a cell, a key, an ammeter, a resistor of 2 \(\Omega\) in series with a combination of two resistors (4 \(\Omega\) each) in parallel and a voltmeter across the parallel combination. Will the potential difference across the 2 \(\Omega\) resistors to be the same as that across the parallel combination of 4 \(\Omega\) resistor? Give reason

2

(a)