Question

The resistance in a circuit is halved. What happens to the voltage?
V=IR
(1 point)
The voltage is increased by a factor of 4.
The voltage remains the same.
The voltage is halved.
The voltage is doubled.

Answer 1

To determine what happens to the voltage when the resistance is halved in a circuit, we can use Ohm's Law, which states:

\[ V = I \times R \]

where \( V \) is the voltage, \( I \) is the current, and \( R \) is the resistance.

If the resistance \( R \) is halved, the equation becomes:

- New resistance \( R' = \frac{R}{2} \)

If the current \( I \) remains constant, the new voltage \( V' \) can be expressed as:

\[ V' = I \times R' = I \times \left(\frac{R}{2}\right) = \frac{I \times R}{2} = \frac{V}{2} \]

This means that if the resistance is halved while the current stays the same, the voltage is also halved.

However, if the current is allowed to change because the resistance is altered (according to Kirchhoff's laws), then we would need more information about the circuit to conclude directly about the voltage.

Assuming a constant current, the correct answer is:

**The voltage is halved.**