In old cartoons, sometimes they would drop a piano on a toon’s head. If a piano weighs 215.5 kg and us falling at a rate of 9.8 m/s^2, what force works it hit the ground with

Brutus, the dog, is pulling a bone to the left with a force of 20 n. lassie, another dog, is pulling a bone to the right with a force of 18n. what is the net force? a. b. c.

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.

Mechanical energy is when there are no forces causing an object to lose energy. a. increased b. conserved c. decreased d. doubled i need this answer ! .