If a 0.8kg ball is thrown with a velocity of 5 m/s, what is its KE?(KE=1/2 x m x v2)

There are weak or strong attractive forces between atoms of liquids with a high viscosity

What object a collides with object b and bounces back its final momentum is?

Consider an insulating crystal, made up of layers of atoms. what form would you expect the temperature dependence of the phonon heat capacity to approach at extremely low temperatures if the interlayer coupling is i)very strong (rigid coupling), and ii) very weak. explain.