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Two people have to each pick up 100 bricks and carry them across the street. One person does this in 1 minute, the other person does it in 100 minutes Who did more work?. Power. Average power = the rate at which work is done P = W/t P = Fd /t Measured in watts (W) 1 W = 1 J/s.
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Two people have to each pick up 100 bricks and carry them across the street. One person does this in 1 minute, the other person does it in 100 minutes • Who did more work?
Power Average power = the rate at which work is done P = W/t P = Fd/t Measured in watts (W) 1 W = 1 J/s
Two people have to each pick up 100 bricks and carry them across the street. One person does this in 1 minute, the other person does it in 100 minutes • Who had more power?
James Watt needed a way to specify the power of his newly developed steam engine. He experimented to find the amount of work a good horse could perform in a specified time period. From his data, he developed: 1 horsepower = 746 W (British: 550 ft-lb/s)
“The Most Powerful Production V8 Engine on Earth” (only $55,000!) • The new Ford Mustang Shelby GT500’s 662 horsepower engine is currently the most powerful V8 car engine. How many watts of power does it produce?
How much work does it do at 662 hp in 5.0 seconds at a constant velocity?
A 70 kg jogger runs up a flight of stairs in 4.0 seconds. The vertical height of the stairs is 4.5 m. What is the jogger’s output of power in watts and hp?
How much power is required for a 1,400 kg car to climb a 10° incline at a steady rate of 80 km/hr? Ignore friction.
Using the last example, calculate the amount of power needed if the coefficient of friction is 0.10.
Bills, bills, bills… • Let’s take a look at how we pay for power…