1. 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

2. Mechanical Advantage What is the mechanical advantage of the following simple machine? GIVEN: d e = 12 m d r = 3 m MA = ? WORK : MA =d e ÷ d r MA = (12 m) ÷ (3 m) MA = 4 MA dede drdr 3 m 12 m

3. Mechanical Advantage Determine the mechanical advantage of an automobile jack that lifts a 9900 N car with an input force of 150 N. GIVEN: F e = 150 N F r = 9900 N MA = ? WORK : MA = F r ÷ F e MA = (9900 N) ÷ (150 N) MA = 66 MA FrFr FeFe

4. Mechanical Advantage Calculate the mechanical advantage of a ramp that is 6.0 m long and 1.5 m high. GIVEN: d e = 6.0 m d r = 1.5 m MA = ? WORK : MA =d e ÷ d r MA = (6.0 m) ÷ (1.5 m) MA = 4 MA dede drdr

5. 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: F e = 20 N F r = 500 N MA = ? WORK : MA = F r ÷ F e MA = (500 N) ÷ (20 N) MA = 25 MA FrFr FeFe

6. D. Mechanical Advantage Find the effort force needed to lift a 2000 N rock using a jack with a mechanical advantage of 10. GIVEN: F e = ? F r = 2000 N MA = 10 WORK : F e = F r ÷ MA F e = (2000 N) ÷ (10) F e = 200 N MA FrFr FeFe

7. Mechanical Advantage What is the mechanical advantage of the following simple machine? GIVEN: F e = 25 N F r = 500 N MA = ? WORK : MA =F r ÷ F e MA = (500N) ÷ (25N) MA = 20 MA FrFr FeFe