Question

If a light bulb uses 0.4 amperes of current at a voltage of 1.8 volts, the formula to find R is , and the resistance of the bulb is ohms. NextReset

Answer 1

R=V/I R=1.8/0.4=4.5ohms

Answer 2

Answer : The resistance of the bulb is 4.5 ohms

Solution :

Using ohm's law,

$V=I\times R\\\\R=\frac{V}{I}$

where,

V = applied voltage = 1.8 volts

I = current = 0.4 amperes

R = resistance

Now put all the given values in the above formula, we get the resistance of the bulb.

$R=\frac{1.8V}{0.4A}=4.5\Omega$

Therefore, the resistance of the bulb is 4.5 ohms