Electric Power (2 of 3) Example Problems

TL;DR

This video provides examples of solving problems using electric power equations.

Transcript

okay for today's video we are going to do a few quick problems using power and the equations that we derived and came up with in the previous video which is linked in the upper right hand corner where I explain what electric power is but in this video we're going to go over some examples alright in the first problem here we're going to calculate el... Read More

Key Insights

• ✊ The equations for electric power include power = current * voltage, power = current^2 * resistance, and power = voltage^2 / resistance.
• ✊ You can calculate the current drawn by a motor using the equation current = power / voltage.
• ✊ The energy used by a device can be found using the equation energy = power * time.
• ✊ The resistance of a component can be determined using the equation resistance = power / (current^2).
• 🔋 The energy produced by a battery can be calculated using the equation energy = power * time.
• ✊ The power rating of a device can be found using the equation power = voltage^2 / resistance.
• ✊ Understanding and using these equations is essential for solving problems involving electric power.

Questions & Answers

Q: How do you calculate the current drawn by a motor with known power and voltage?

To calculate the current, you can use the equation current = power / voltage. Plug in the values and divide to find the current drawn.

Q: How can you find the energy used by a hairdryer over a given time?

By using the equation energy = power * time, you can multiply the power rating of the hairdryer by the time used to find the energy consumed.

Q: How do you determine the resistance of a light bulb with known power and current?

The resistance can be found using the equation resistance = power / (current^2). Divide the power by the square of the current to find the resistance.

Q: How can you calculate the energy produced by a battery to start a car engine?

By using the equation energy = power * time and substituting the known values of current, voltage, and time, you can find the energy produced by the battery.

Summary & Key Takeaways

• The video starts by explaining the equations for electric power.

• The first example calculates the current drawn by a motor based on power and voltage.

• The second example finds the energy used by a hairdryer over a given time.

• The third example determines the resistance of a light bulb with known power and current.

• The fourth example calculates the energy produced by a battery to start a car engine.

• The final example calculates the power rating of an immersion heater using voltage and resistance.