Short notes
Objective questions (Answers are given below)
- If a 220 V heater is used on 110 V supply,
heat produced by it will be —— as much.
(a) one-half (b) twice
(c) one-fourth (d) four times - For a given line voltage, four heating coils
will produce maximum heat when connected
(a) all in parallel (b) all in series
(c) with two parallel pairs in series
(d) one pair in parallel with the other two
in series - The electric energy required to raise the temperature
of a given amount of water is 1000
kWh. If heat losses are 25%, the total heating
energy required is — kWh.
(a) 1500 (b) 1250
(c) 1333 (d) 1000 - One kWh of energy equals nearly
(a) 1000 W (b) 860 kcal
(c) 4186 J (d) 735.5 W - One kWh of electric energy equals
(a) 3600 J (b) 860 kcal (c) 3600 W (d) 4186 J - A force of 10,000 N accelerates a body to velocity 0.1 km/s. This power developed is —— k (a) 1,00,000 (b) 36,00 (c) 3600 (d) 1000
- A 100 W light bulb burns on an average 10 hours a day for one week. The week consumption of energy will be —— unit (a) 7 (b) 70 (c) 0.7 (d) 0.07
- Two heaters, rated at 1000 W, 250 volts each are connected in series across a 250 Volt 50 Hz A.C. mains. The total power drawn from the supply would be ——— watt. (a) 1000 (b) 500 (c) 250 (d) 2000
1.c
2. a
3. c
4. b
5. b
6. d
7. a
8. b