The shopper pays for his groceries and pushes the shopping cart out of the store, where he encounters a ramp that him move the cart from the sidewalk down to the parking lot. what force accelerates the cart down the ramp?

Which best represents the law of conservation of mass ?

In science and physics what is the standard unit of measure for speed?

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.