A 1.0 kg red ball moving at 5.0 m/s [East 30 degrees North] collides head-on with a blue ball of mass 4.0 kg in an inelastic collision. The blue ball was initially moving at 3.5 m/s [West 40 degrees North]. What is the final velocity of: (a) the red and blue ball?
(b) the blue ball?

Asample of a gaseous substance changes into a liquid

The speed of light in a material is 0.50 c. what is the critical angle of a light ray at the interface between the material and a vacuum?

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?