The current in a light bulb is 2 A. How long does it take for a total charge of 4 C to pass a point in the wire

If an athlete runs once around a track, back to the starting line, her average velocity is zero. true or false?

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.

An object is kept at 45 m high and how much time will it take to reach the ground