Which one of the following is not a simple machine?
a. lever
b. pulley
c. hammer
d. inclined plane user: an input force of 20 newtons is applied to a lever at a distance of 2 meters from the fulcrum. an object 0.5 m away from the fulcrum (and on the other side) is lifted by the 20-n force. what is the output force?
a. 10 n
b. 20 n
c. 40 n
d. 80 n

Ahorizontal wire is tied to supports at each end and vibrates in its second-overtone standing wave. the tension in the wire is 5.00 n, and the node-to-node distance in the standing wave is 6.28 cm. (a) what is the length of the wire? (b) a point at an anti- node of the standing wave on the wire travels from its maximum upward displacement to its maximum downward displacement in 8.40 ms. what is the wire's mass?

The boy of mass 30 kg is at r1= 2 meters from the fulcrum. of the girl is 45 kg, at what r2 must she sit so that they are balanced ?

In a stagnant pool of water, a crayfish may spend much of its time lying with one side of its carapace near the surface of the water. in this position, it will move the walking legs on that side in a rhythmic back-and-forth motion. explain the likely function of this behavior.