A25.0 kg projectile is fired by accelerating it with an electromagnetic rail gun on the earth's surface. the rail makes a 30.0 degree angle with the horizontal, and the gun applies a 1250 n force on the projectile for a distance of 7.50 m along the rail. (a) ignoring air resistance and friction, what is the net work done on the projectile, by all the forces acting on it, as it moves 7.50 m along the rail? (b) assuming it started at rest, what is its speed after it has moved the 7.50 m?

The 5-kg cylinder is initially at rest when it is placed in contact with the wall b and the rotor at a. if the rotor always maintains a constant clockwise angular velocity v = 6 rad> s, determine the initial angular acceleration of the cylinder. the coefficient of kinetic friction at the contacting surfaces b and c is mk = 0.2.

Ais not a compound machine. a. bolt b. shovel c. handcart (dolly) d. see-saw (teeter totter)

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.