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What two things need to occur for work to be done on an object?. An object must move a distance as a result of a force The force exerted must be in the same direction as the objects motion. What is another name for a joule?. a newton -meter.
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What two things need to occur for work to be done on an object? • An object must move a distance as a result of a force • The force exerted must be in the same direction as the objects motion
What is another name for a joule? a newton-meter
A cyclist exerts a force of 40 newtons for a distance of 5 meters. How much work was done by the cyclist? 40N X 5 m = 200 joules or newton-meters
What is the formula for work? Force times distance
What is the formula for finding power? Power = work divided by time
The amount of work done in lifting four 10-N sacks of oranges 3 meters is the same as lifting two 30 N sacks of apples how far? 2 meters
Two dogs are digging separate holes in the ground. Sydney does 300 j of work in 3 seconds and duke does 300 j of work in 4 seconds. What is the difference between the two? Power – 25 watts
A motor on a boat exerts a force of 2,000 newtons. It propels the boat 12 meters in 8 seconds. What is the power output? (2000 X 12) divided by 8 =3000 watts
Define power The rate at which work is done
A steel box with a mass of 10kg was lifted 3 meters in 4 seconds.How much force was used? 10 X 9.81 = 98.1 newtons
A steel box with a mass of 10kg was lifted 3 meters in 4 seconds.How much work was performed? (10 X 9.31) X 3 = 294.3 joules
A steel box with a mass of 10kg was lifted 3 meters in 4 seconds.How much power was used? (10 X 9.81) X 3 divided by 4 = 73.575w