Force, Work, Power and Energy
Work, Power and Energy
Refraction of Light Through Plane Surface
Refraction of Light Through a Lense
Electricity and Magnetism
Electrical Power and Energy and Household Circuits
- Concept of Electrical Power and Household Circuits Numericals
- Household Circuits - Colour Coding of Wires
- Household Circuits - Three-pin Plugs
- Household Circuits - Safety Precautions
- Earthing (Grounding)
- Electric Switch
- Household Circuits – Main Circuit
- Electrical Energy and Power
- Electric Power
- Alternating Current (A.C.) Generator
- Current Electricity
- Resistors in Series
Three heaters each rated 250 W, 100 V are connected in parallel to a 100 V supply. Calculate:
(i) the total current taken from the supply
(ii) the resistance of each heater and
(iii) the energy supplied in kWh to the three heaters in 5 hours.
The diagram above shows a circuit with the key k open. Calculate :
(i) the resistance of the circuit when the key k is open.
(ii) the current drawn from the cell when the key k is open.
(iii) the resistance of the circuit when the key k is closed.
(iv) the current drawn from the cell when the key k is closed.
An electric toaster draws 8 A current in a 220 V circuit. It is used for 2 h. Find the cost of
operating the toaster if the cost of electrical energy is Rs. 4.50 per kWh.
An electric bulb is rated 250 W, 230 V calculate:
(i) the energy consumed in one hour
(ii) the time in which the bulb will consume 1.0 kWh energy when connected to 230 V mains.
Calculate the current through a 60 W lamp rated for 250 V. If the line voltage falls to 200 V, how is the power consumed by the bulb affected?