MCQ
An electric heater is heated by de and ac respec- tively. The potential difference applied across the ends of heater for both ac and de is same. Heat gener- ated per second will be more:
  • A
    On heating with ac
  • B
    On heating with de
  • Same in both
  • D
    None of the above two

Answer

Correct option: C.
Same in both
(c)Same in both

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

50% of the X-ray coming from a Coolidge tube is able to pass through a 0.1mm thick aluminium foil. The potential difference between the target and the filament is increased. The thickness of the aluminium foil that will allow 50% of the X-ray to pass through will be:

A cable of resistance 10 Ω carries electric power from a generator producing 250 kW at 10000 volt. The current in the cable is

(a) 25 A   

(b) 250 A

 

(c) 100 A 

(d) 1000 A

An electron makes a transition from orbit n = 4 to the orbit n = 2 of a hydrogen atom. The wave number of the emitted radiations (R = Rydberg's constant) will be

(a)  

(b)  

(c)          

(d) 

Find x in the following nuclear reaction.
2​He13​Al27 → x​P30 0​n1
A hank of uninsulated wire consisting of seven and a half turns is stretched between two nails hammered into a board to which the ends of the wire are fixed. The resistance of the circuit between the nails is determined with the help of electrical measuring instruments. Determine the proportion in which the resistance will change if the wire is unwound so that the ends remain to be fixed to the nails.
An $\alpha$-particle is bombarded on 14N. As a result, a 17O nucleus is formed and a particle is emitted. This particle is a:
In a cathode ray oscillograph, the focusing of beam on the screen is achieved by:
A circular current loop of magnetic moment M is in an arbitrary orientation in an external magnetic field B. The work done to rotate the loop by 30° about an axis perpendicular to its plane is:

A condenser having a capacity of 6mF is charged to 100 V and is then joined to an uncharged condenser of 14 μF  and then removed. The ratio of the charges on 6mF  and 14mF  and the potential of 6mF will be

(a)  and 50 volt

(b)  and 30 volt

(c)  and 30 volt

(d)  and 0 volt

A lens behaves as a converging lens in air and a diverging lens in water. The refractive index of the material is

(a) Equal to unity

(b) Equal to 1.33

(c) Between unity and 1.33

(d) Greater than 1.33