(a)  ultrasonic waves
         (b)  infrasonic waves
         (c)  radio waves
         (d)  audible sound waves
Ans : (a)
313. When you pull out the plug connected to an electrical appliance, you often observe a spark. To which property of the appliance is
     this related? [CDS 2011]
       (a) Resistance
       (b) Inductance
       (c) Capacitance
       (d) Wattage
Ans : (c)
314. If the door of a running refrigerator in a closer room is kept open, what will be the net effect on the room? [CDS 2011]
       (a) It will cool the room
       (b) It will heat the room
       (c) It will make no difference on the average
       (d) lt will make the temperature go up and down
Ans : (b)
315. When a ball drops onto the floor it bounces. Why does it bounce? [CDS 2011]
       (a) Newton"s third law implies that for every action (drop) there is a reaction (bounce)
       (b) The floor exerts a force on the ball during the impact
       (c) The floor is perfectly rigid
       (d) The floor heats up on impact
Ans : (a)
316. A body has a mass of 6 kg on the Earth; when measured on the Moon, its mas would be [CDS 2011]
       (a) Nearly 1 kg
       (b) less than 1 kg
       (c) less than 6 kg
       (d) 6 kg
Ans : (d)
317. Transformer is a kind of appliance that can
       1) increase power
       2) increase voltage
       3) decrease voltage
       4) measure current and voltage
       Select the .correct answer using the code given below: [CDS 2011]
       (a)   1 and 4
       (b)   4 only
       (c)   2 and 3 only
       (d)   2, 3 and 4
Ans : (c)
318. At the time of short-circuit the current in the circuit [Asstt Commdt 2011]
       (a) reduces substantially
       (b) does not change