ICSE − Q & A

MCB and ELCB 4 differences please?

Does the frequency of the forced vibration have to be the same or a multiple of the natural frequency of the body on which the forced vibration is being applied for resonance??Plz reply ASAp....

You r given half litre of water at 20 degree Celsius. Which process (boiling off completely or bringing to its boiling point will take more time.  Explain

Can some1 explain why the critical angle of light in a medium decreases with decrease in temperature??

. How will the Centre of gravity of a symmetrical cylinder change if it is one fourth filled with water. Justify.

Can anyone explain me Faraday's  explanation for the phenomenon of electromagnetic induction..plzz..as soon as possible...??

what is the formula of voltage drop?

Listen everyone, I'd like to ask you all if double pole switch working should be considered important ??? REPLY FREELY IF ANYONE OF YOU Feel it important for the exam  ?? Be Quick please !!!

Does body always vibrate with its own natural frequency  and amplitude no matter how hard it may be struck?If yes then can any1 tell me how forced vibrations are different??? If no then can any1 elaborate on free and forced vibrations by bringing imp points of difference? Plzzz ASAP

Guy please reply to these questions ASAP:
1)How will the Centre of gravity of a symmetrical cylinder change if it is one fourth filled with 
water. Justify.
2) Mention any two differences between reflection of light from plane mirror and total internal 
reflection of light from a prism.
3)Define absolute refractive index. Can it be less than one? Explain.
4)Define one diopter.
5) Name two waves of frequency greater than of violet light. State one use of each.