Question

A 12.0 V car battery is being used to power the headlights of a car. Each of the two headlights has a power rating of 41.8 Watts. The number of electrons that pass through the car battery each second is ___ x 1019. Assume three significant digits in your answer. You do not need to use scientific notation when you enter your answer.

Answer 1

Answer:

n = 4.35 x 10¹⁹          

Explanation:

Given that

Voltage V= 12 V

Power rating of headlights = 41.8 W

We know that headlights of the car is connected in parallel connection.

We know that

Power = Current x Voltage

P = V I

$I=\dfrac{41.8}{12}\ A$

I=3.48  A

Therefore the total current will be

I'= 3.48 + 3.48 A

I = 6.96 A

We know that

Charge = Current x time

q= I' t

q= 6.96 x 1

q= 6.96 C

The charge on electron ,e= 1.6 x 10⁻¹⁹

q= n e

n=Number of electron

$n=\dfrac{q}{e}$

$n=\dfrac{6.96}{1.6\times 10^{-19}}$

n = 4.35 x 10¹⁹