An 8.0g bullet is fired horizontally into a 9kg block of wood on a frictionless table and is embedded in it. after the collis6, the block and the bullet slide ,along the surface together with a speed of 10cm/s.

a. find the initial speed

b. find the kinetic energy of the system before collision

c. find the kinetic energy of the system after collision

d. what percentage of the systems original kinetic energy was lost

if you can.

Moon effect. some people believe that the moon controls their activities. if the moon moves from being directly on the opposite side of earth from you to being directly overhead, by what percentage does (a) the moon's gravitational pull on you increase and (b) your weight (as measured on a scale) decrease? assume that the earth–moon (center-to-center) distance is 3.82 × 10^8 m, earth's radius is 6.37 × 10^6 m, moon's mass is 7.36 × 10^22 kg, and earth's mass is 5.98 × 10^24 kg.

Electromagnetic induction. a coil of wire contains n turns and has an electrical resistance r. the radius of each turn is a. initially, inside the coil there exists a uniform magnetic field of magnitude b0 parallel to the axis of the coil. the magnetic field is then reduced slowly. the current induced in the coil is i. how long does it take for the magnitude of the uniform field to drop to zero?

It is really hard for me right know