A particle which has zero rest mass and non - zero energy and momentum must travel with a speed

The particle which has zero mass but has energy is

A particle having almost zero mass and exactly zero charge is

Statement I : A particle with zero velocity may have a non - zero acceleration. Statement II : A particle comes to rest at the instant of reversing its direction of motion.

Speed is always non-zero.

A particle has a linear momentum p and position vector r. the angular momentum of this particle about the origin will not be zero under the conditions

A particle has a linear momentum p and position vector r. the angular momentum of this particle about the origin will not be zero under the conditions