When you sit on your chair, you exert a downward force on the chair which we call an action force. According to Newton's 3rd law, what is the reaction force?

Consider a double atwood machine constructed as follows: a mass 4m is suspended from a string that passes over a massless pulley on frictionless bearings. the other end of this string supports a second similar pulley, over which passes a second string supporting a mass of 3m at one end and m at the other. using two suitable generalized coordinates, set up the lagrangian and use the lagrange equations to find the acceleration of the mass 4m when the system is released. explain why the top pulley rotates even though it carries equal weights on each side.

Both speed and velocity measure how fast something is moving. however, since speed is not a it does not require a(n question 6 options: a) quantity , unit b) magnitude, unit c) scalar, direction d) vector, direction

Ahurricane sweeps across the ocean and damages the houses of people living along the coast. which of these does not play any role in this interaction? air water glaciers living things