Understanding Electrical Power Concepts

The video tutorial explains the concept of power as the rate of energy usage, using examples like weightlifting and electric power. It introduces James Watt's contributions and the term 'horsepower'. The tutorial covers the calculation of electric power using voltage and current, and discusses power consumption and energy conversion in devices like resistors and incandescent bulbs. Practical applications of power in everyday devices such as toasters and space heaters are also explored.

What is the term used to describe the rate at which energy is used?

• Speed

• Power

• Force

• Work

Who coined the term 'horsepower'?

• Isaac Newton

• Nikola Tesla

• James Watt

• Michael Faraday

If it takes 3 seconds to expend 900 joules of energy, how much power is needed?

• 300 watts

• 200 watts

• 100 watts

• 400 watts

What is the SI unit for power?

• Joule

• Watt

• Ampere

• Volt

How is electric power calculated?

• Voltage divided by current

• Current divided by voltage

• Voltage times current

• Voltage plus current

What happens to electrical energy in a resistor?

• It is converted to light

• It is stored

• It is converted to heat

• It is destroyed

What does an infrared thermometer measure?

• Voltage

• Current

• Surface temperature

• Power

What is the primary function of a filament in an incandescent light bulb?

• To convert electrical energy to light

• To convert electrical energy to sound

• To store electrical energy

• To convert electrical energy to motion

Why are incandescent bulbs considered inefficient?

• They convert most electrical energy to motion

• They convert most electrical energy to sound

• They convert most electrical energy to light

• They convert most electrical energy to heat

Which household device relies on resistive elements to function?

• Washing machine

• Toaster

• Microwave

• Refrigerator