Question

the potential difference between the terminals of an electric heater is 120 v when it draws a current of 6A from the source what current will be the heater draw if the potanical difference is increased to 240v.
Correct answer will be marked as the brainlyest ​

Answer 1

Given that, potential difference between the terminals of an electric heater is 120 V

(Potential difference i.e. V = 120V)

Also, it draws a current of 6A.

(Current i.e. I = 6A)

We have to find the current that will the heater draw if the potential difference is increased to 240V.

Using Ohm's Law

V = IR

Substitute the known values

120 = 6 × R

120/6 = R

20 = R

Therefore, the resistance (R) is 20 Ω.

Now,

V = 240V (Potential difference is increased by 240V)

From the above calculations, we have R = 20Ω.

We have to find the current (I), according to question.

I = V/R

Substitute the values

I = 240/20

I = 12A

Therefore, the current of 12A, the heater will draw if the potential difference is increased to 240v.

(Current is drawn double by heater when the potential difference across the heater is doubled.)

Answer 2

Given:-

The potential difference between the terminals of an electric heater is 120 V when it draws a current of 6 A from the source.

To find:-

The amount of current that the heater will draw if the potential difference is increased to 240 V.

Solution:-

P.D. = 120 V

I = 6 A

By Ohm's law,

potential difference = Resistance*Current

V = IR

⇒120 = 6*R

⇒R = 120/6

⇒R = 20 Ω

now, the resistance (R) is 20 Ω.

P.D. = 240 V (Potential difference is increased to 240 V)

R = 20 Ω

I = ?

V = IR

⇒I = V/R

⇒I = 240/20

⇒I = 12 A

∴Therefore, the heater will draw a current of 12 A if the potential difference is increased to 240 V.

• Thus, we conclude that, the current gets doubled when the potential difference is doubled. Ohm's law is verified.