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Formulas guide our thinking. RHS SCIENCE TAKS REVIEW. WORK, POWER, AND ENERGY. Work. Work = Force x distance. Work is force applied over a distance. W = F d. The unit of work is the joule (J) 1J = 1N x 1m. CHECK FOR UNDERSTANDING.
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Formulas guide our thinking RHSSCIENCETAKS REVIEW WORK, POWER, AND ENERGY
Work • Work = Force x distance • Work is force applied over a distance. W = F d The unit of work is the joule (J) 1J = 1N x 1m
CHECK FOR UNDERSTANDING If you use a 20N force to move a box 13.7 m, how much work do you do? W = Fd = 20N x 13.7m = 274 N.m = 274J
Work Time Power • Power = • Is the rate at which work is done.
The Unit of Power is the WATT 1 watt = 1 joule of work done in 1 second watt = joule/second
CHECK FOR UNDERSTANDING A crane lifts an 800-N crate 75 m in 30 s. How much power does the crane use? Hint:First solve for work
W = F x d W = 8000 N x 75 m W = 600,000 N·m = 600,000 J Solution P = W/t P = 600,000 J /30 s = 20,000 J/s = 20,000 W