The 9 kg block is then released and accelerates
to the right, toward the 2 kg block. the
surface is rough and the coefficient of friction
between each block and the surface is 0.5. the
two blocks collide, stick together, and move
to the right. remember that the spring is not
attached to the 9 kg block.
find the speed of the 9 kg block just before
it collides with the 2 kg block.
answer in units of m/s.

Ametal ring 4.20 cm in diameter is placed between the north and south poles of large magnets with the plane of its area perpendicular to the magnetic field. these magnets produce an initial uniform field of 1.12 t between them but are gradually pulled apart, causing this field to remain uniform but decrease steadily at 0.240 t/s . (a) what is the magnitude of the electric field induced in the ring? (b) in which direction (clockwise or counterclockwise) does the current flow as viewed by someone on the south pole of the magnet?