The power of a heater is 500W at `800^(@)C`. What will be its power at `200^(@)C` it `alpha=4xx10^(-4)` per `.^(@)C`?

The power of a heater is 500W at 800^(@)C what will be its power at 200^(@)C . If alpha= 4 xx 10^(-4)//C^(0)

The resolving power of a microscope at 6000 Å is 10^(4) . What is its resolving power at 4000 Å

The power of 7 contained in ""^(1000)C_(500) must be

One kilowatt electric heater is to be used with 220V d.c. supply. (i) What is the current in the heater? (ii) What is lts resistance? (iii) what is the power dissipated in the heater? (iv) How much heat in calories is produced per second? (v) How many grams of water at 100^(@)C will be converted per minute into steam at 100^(@)C , with the heater? Assume that the heat losses due to radiation are negligible. Latent heat of steam=540cal per gram.

One kilowatt electric heater is to be used with 220V d.c. supply. (i) What is the current in the heater? (ii) What is lts resistance? (iii) what is the power dissipated in the heater? (iv) How much heat in calories is produced per second? (v) How many grams of water at 100^(@)C will be converted per minute into steam at 100^(@)C , with the heater? Assume that the heat losses due to radiation are negligible. Latent heat of steam=540cal per gram.

The resolving power of a microscope at 6000 overset(@)A is 10^4 . What is its resolving power at 4000 overset(@)A ?

At what temperature will the resistannce of a copper wire become three times its value at 0^(@)C (Temperature coefficient of resistance for copper =4xx10^(-3)"per".^(@)C :-

At what temperature will the resistannce of a copper wire become three times its value at 0^(@)C (Temperature coefficient of resistance for copper =4xx10^(-3)"per".^(@)C :-