Question

ressistance of the 230 voltage heating devices is 460 ohm.calculate the heat energy produced by it 60 minutes?

Answer 1

Answer:

Solution : W=V2tR=(220V)2(12×60s)25Ω=1393920J=1393.92kJ.

Answer 2

Answer:

$\bigstar{\bold{Heat\:energy=414000\:J}}$

Explanation:

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

• Resistance (R) = 460 Ω
• Potential difference (V) = 230 V
• Time taken (t) = 60 min = 3600 s

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

• Heat energy (H)

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

→ First we have to find the current (I) flowing through the device

→ By Ohm's law current flowing through is given by the formula,

  V = I R

→ Substituting the datas, we get the value of I,

  230 = I × 460

       I = 230/460

       I = 0.5 A

→ By Joule's law heat produced is given by the formula,

  H = I² R t

→ Substitute the datas,

  H = (0.5)² × 460 × 3600

  H = 0.25 × 460 × 3600

  H = 414000 J

→ Hence heat produced = 414000 J

$\boxed{\bold{Heat\:energy=414000\:J}}$

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

→ Ohm's law state that the current flowing through a conductor is directly proportional to potential difference applied across its ends provided the temperature and other physical factors remain unchanged.

V = R I

→ Joule's law state that heat dissipated in a conductor is directly proportional to the square of the current flowing through the conductor, resistance of the conductor, time for which current flows through the conductor.

H = I² R t