Question

7. An electric heater works on 230V

A current of 6A flows through this for 10min.
Calculate the amount of heat energy generated​

Answer 1

Answer:

given potential difference = 230v

current = 6A

time. 10 min

resistance = v/i

=230/6

=115/3

heat energy = i*i *R*t

=6*6*600*115/3

=12*600*115

=828000j

Answer 2

Answer:

$\bigstar{\bold{Heat\:energy=827.928\:kJ}}$

Explanation:

$\Large{\underline{\underline{\sf{Given:}}}}$

• Potential Difference (V) = 230 V
• Current (I) = 6 A
• Time taken (t) = 10 min = 600 s

$\Large{\underline{\underline{\sf{To\:Find:}}}}$

• Heat energy generated

$\Large{\underline{\underline{\sf{Solution:}}}}$

→ First we have to find the resistance of the electric heater.

→ By Ohm's law we know that,

  R = V/I

→ Substituting the datas we get the value of resistance

   R = 230/6

   R = 38.33 Ω

→ Hence resistace of the conductor is 38.33 Ω

→ The heat enery dissipated is given by Joule's law,

  H = I² R t

→ Substitute the datas,

  H = 6 × 6 × 38.33 × 600

  H  = 36 × 22998

  H = 827928 J = 827.928 kJ

→ Hence the heat energy generated by the conductor is 827.928 kJ

$\boxed{\bold{Heat\:energy=827.928\:kJ}}$

$\Large{\underline{\underline{\sf{Notes:}}}}$

→ Resistance of a conductor is directly proportional to its length and inversely proportional to the area of cross section.

  R = ρ L/ A

  where L is the length and A is the area of cross section.

→ Ohm's law is given by

  V = I R

  where V is the potential difference, I is the current and R is the resistance.

→ Joule's law is given by

  H = I² R t

  where H is the heat energy, I is the current, R is the resistance and t is the time in seconds.