Question

a current of 0.45 ampere flowing in a resistor dissipate 100 joule of energy in one second calculate the resistance of resistor

Answer 1

energy = power * time

100 = power * 1

therefore power = 100w

now

power = volt / current

100 = volt / .45

volt = 100 * .45 = 45 volt

so now resistance is

resistance = volt * current

that is

45 * .45 = 20.25 ohm

i think this is the answer friend but do consider verification with ur teacher

Answer 2

Energy of 100J in one second means a power of 100 W.

Therefore,

⇒ P = 100W,

    I = 0.45A

Now,

P= I² R

⇒ R = P/I²

⇒ P/I² = 100/(0.45)²

∴ Resistance = 493 Ω

Hope this helps!

Regards,

Soham Patil.