MCQ

1. The best conductor of heat among liquids is (a) water (b) mercury (c) ether (d) alcohol 2. The layer of the atmosphere which reflects ratio waves back to the earth is called (a) Stratosphere (b) Tropopause (c) Ionosphere (d) Troposphere 3. An object weigth maximum in (a) air (b) water (c) hydrogen (d) vacuum […]

Refrigeration| MCQ 1. A one tonne refrigerating machine means that (a) the total weight of the machine is one tonne. (b) the quantity of the refrigerant used is one tonne. (c) one tonne of water can be converted into ice. (d) one tonne of ice when melts from and at 0°C in 24 hours, the

1. A transformer will work on  (i) a.c. only (ii) d.c. only (iii) a.c. as well as d.c (iv) none of the above 2. The primary and secondary of a transformer are ……… coupled. (i) electrically (ii) magnetically (iii) electrically and magnetically (iv) none of the above 3. A transformer is an efficient device because

1. The yoke of a d.c. machine is made of (i) silicon steel (ii) soft iron (iii) aluminium (iv) cast steel 2. The armature of a d.c. machine is made of (i) silicon steel (ii) wrought iron (iii) cast steel (iv) soft iron 3. The coupling field between electrical and mechanical systems of a d.c.

1. An ammeter is …………… instrument. (i) an indicating (ii) an integrating (iii) a recording (iv) none of the above 2. The controlling torque of an indicating instrument ………. as the deflection of the moving system increases. (i) remains unchanged (ii) decreases (iii) increases (iv) none of the above 3. When the pointer of an

1. In Fig. given below, the magnetic circuit is the path (i) DAB (ii) ABCDA (iii) ABC (iv) ABCD 2. If l is the magnetic path in the above Fig., then magnetising force is (i) Nl (ii) Nl x l (iii) l ÷ NI (iv) NI ÷ l 3. The reluctance of the magnetic circuit

1. The force between two electrons separated by a distance r varies as (i) r2 (ii) r (iii) r-1 (iv) r-2 2. Two charges are placed at a certain distance apart. A brass sheet is placed between them. The force between them will (i) increase (ii) decrease (iii) remains unchanged (iv) none of the above

1. A kilowatt hour is the unit of (i) energy(ii) power(iii) electric charge(iv) electric current 2. Heat produced in a conductor depends (i) inversely on time(ii) directly on time(iii) both (i) and (ii)(iv) none of the above 3. If potential difference across a conductot of a material of resistivity ρ remains constant, then heat produced

1. The diameter of an atom is about (i) 10-10 m (ii) 10-8m (iii) 10-2 m (iv) 10-15 m 2. The number of compounds available in nature is (i) 105 (ii) 300 (iii) 1000 (iv) unlimited 3. The mass of a proton is …….. the mass of electron. (i) equal to (ii) less than (iii)

The demand for electrical energy is increasing day by day. So a boom in the consumption of electrical energy has been seen in the last few decades. It is the very reason for the growth in the field of electrical engineering. Due to this growth, carriers in this field are increasing day by day. Almost