Assuming the lower arm has a mass of 2.8 kg and its Center of Gravity is 12 cm from the elbow-joint pivot, how much force must the extensor muscle in the upper arm exert on the lower arm to hold a 7.5 kg shot put

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

Which configuration would produce an electric current? a) rotate a coil of copper wire between two magnets. b) connect a wire between a copper and zinc strip sitting in a beaker of water. c) connect a wire to the (+) positive end of a battery and the other end to a light bulb. d) connect a wire to the negative end of a battery and the other end to a light bulb.

You've already seen the value of 9.8 in this lesson. what's this value called? what quantity does it represent?