Question

When a 6v battery is connected arcross an unknown
resistor a there is a current of 300m A in the
circuit. Find the value of the resistance of the
resistor​

Answer 1

Guven :-

Potential difference (V) = 6V

Current (I) = 300 mA

To find :-

The resistance of resister

According to the formula

$\boxed{\sf \ V= IR}$

Convert current into Ampere It is given in milliampere !

$\sf \ 1\ mA= 10^{-3}A\\ \\ \longrightarrow\sf 300\ mA= 300\times 10^{-3}\ A \\ \\ \longrightarrow\sf I= 0.3 A$

Now find the resistance

$\longrightarrow\sf R= \dfrac{V}{I}\\ \\ \longrightarrow\sf R= \dfrac{6}{0.3}\times \dfrac{10}{10}\\ \\ \longrightarrow\sf R= \cancel{\dfrac{60}{3}}\\ \\ \longrightarrow\sf R= 20 \Omega$

$\boxed{\sf\ \ Resistance = 20 \Omega}$

Answer 2

Resistance of resistor = 20Ω

Solution

We have,

Potential difference = 6 V

Current = 300 m A

Resistance = ?

Here, current is 300m A

[1 m A = 1/10³ A]

⇒ Current = 300/10³

⇒ Current = 300/1000

⇒ Current = 0.3 A

We will apply ohm's law in this to find resistance.

According to ohm's law :-

⊕ Potential difference = Current × Resistance

⇒ 6 = 0.3 × Resistance

⇒ Resistance = 6/0.3

⇒ Resistance = 60/3

⇒ Resistance = 20Ω

∴ Resistance of resistor = 20Ω