Mechanical advantage The number of times a force
Mechanical advantage • The number of times a force exerted on a machine is multiplied by the machine • Mechanical advantage (MA). = resistance force effort force • Mechanical advantage (MA) = effort distance resistance distance
Mechanical Advantage What is the mechanical advantage of the following simple machine? 12 m GIVEN: WORK: de = 12 m dr = 3 m MA = ? MA =de ÷ dr MA = (12 m) ÷ (3 m) MA = 4 de MA dr 3 m
Mechanical Advantage Determine the mechanical advantage of an automobile jack that lifts a 9900 N car with an input force of 150 N. GIVEN: WORK: Fe = 150 N Fr = 9900 N MA = ? MA = Fr ÷ Fe MA = (9900 N) ÷ (150 N) MA = 66 Fr MA Fe
Mechanical Advantage Calculate the mechanical advantage of a ramp that is 6. 0 m long and 1. 5 m high. GIVEN: WORK: de = 6. 0 m dr = 1. 5 m MA = ? MA =de ÷ dr MA = (6. 0 m) ÷ (1. 5 m) MA = 4 de MA dr
D. Mechanical Advantage • A worker applies an effort force of 20 N to open a window with a resistance force of 500 N. What is the crowbar’s MA? GIVEN: WORK: Fe = 20 N Fr = 500 N MA = ? MA = Fr ÷ Fe MA = (500 N) ÷ (20 N) MA = 25 Fr MA Fe
D. Mechanical Advantage • Find the effort force needed to lift a 2000 N rock using a jack with a mechanical advantage of 10. GIVEN: WORK: Fe = ? Fr = 2000 N MA = 10 Fe = Fr ÷ MA Fe = (2000 N) ÷ (10) Fe = 200 N Fr MA Fe
Mechanical Advantage What is the mechanical advantage of the following simple machine? GIVEN: WORK: Fe = 25 N Fr = 500 N MA = ? MA =Fr ÷ Fe MA = (500 N) ÷ (25 N) MA = 20 Fr MA Fe
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