what is the input and output force for the following simple machines?

Question

wheel/axle, lever, pulley, inclined plane, screw
any others are great i need to identify input/output force for each please help i understand what input/output force is but i cant identify it for the simple machines thank you so much

Answer 1

All these machines have a certain RATIO of input force to output force, referred to as the "mechanical advantage". Take a simple lever. You can use it to increase force while decreasing the amount of motion (as in prying up a rock) or increase motion while decreasing force (as in an oar on a boat). The input force Fi is the force you apply to the lever and the output force Fo is the force the lever applies to the load (rock, water, etc.). The ratio Fo/Fi = the length of the lever on your side of the fulcrum, Li / the length of the lever on the work side of the fulcrum, Lo. Assuming no friction you can see that the lever neither dissipates nor generates energy. (Fo/Fi = Li/Lo, so energies Fi*Li*lever motion angle and Fo*Lo*lever motion angle are equal.)
The wheel and (rigidly attached) axle are a rotary form of the simple lever, where Li and Lo are the radii of the wheel and of the axle. By the same logic, a pair of meshed gears also forms a lever.
Note that Fi and Fo are not necessarily applied on opposite sides of the fulcrum. The fulcrum can be on one end of the lever. But what is handy about having the forces on opposite sides of the fulcrum is the reversal of direction of motion. Many lever jobs involve lifting heavy objects. Using your own body weight (a downward Fi) to do the lifting is much easier than heaving upward is.
The inclined plane or wedge is almost always used in the mode that increases force although it could be used the other way if friction were low enough. Fo/Fi =1/TAN(wedge angle).
A screw can be considered an inclined plane wrapped around a shaft. Taken by itself, when used in the most common mode it requires an input of torque (Ti), not force. Fo = Ti * 2 * pi / thread spacing. Add a crank handle of length C to the screw and you provide a means of inputting Fi. Then Fo = Fi * C * 2 * pi / thread spacing.
Like inclined planes, pulleys are almost always used in the force-increasing mode. If you merely look at the forces on each end of the rope, a single-sheave pulley has no mechanical advantage; the forces are equal. You have to attach the pulley to the load you want to move, and tie one end of the rope to an immovable object, to get a 2:1 mechanical advantage. When you apply Fi to the free end of the rope, both you and the immovable object are applying Fi to the load via the pulley. Pulleys can be arranged in many compound forms. See the ref.

Answer 2

a bike