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How does power change with voltage?

Answer 1

Leo Abeyta

Power #P# is related to voltage #V# and current #I# as:

# P = V * I #

So the power will increase proportionally with the voltage if I is constant.

This is because power is defined as energy consumed per second as stated in the equation:

# P = E/t # where E is energy and t is time.

Voltage is defined as the amount of energy per charge:

# V = E / Q # where Q is the amount of charge in Coulumbs and E is the amount of energy in Joules.

Current is defined as the the flow of charge per unit time:

# I = Q/t #

So when we multiply #V*I# we get:

#V * I = E/Q * Q/t = E/t = P#

We can also find Power from voltage and resistance because we know from Ohm's law that:

# I = V/R # and so electric power can be related to voltage and resistance as:

# P = V*I = V*V/R = V^2/R #

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Answer 2

Amelia Adams

Power changes with voltage according to the formula P = V^2 / R, where P is power in watts, V is voltage in volts, and R is resistance in ohms. This equation illustrates that power is directly proportional to the square of the voltage, meaning that as voltage increases, power increases exponentially.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.