Question

If there is an option for the soldiers to use rifles of
different weights but with bullets of a fixed weight,
they would prefer
(1) Light guns because they can be carried easily
(2) Light guns so that they can be held firmly
(3) Heavy guns because they have less recoil
velocity
(4) Light guns because they have more recoil
velocity​

Answer 1

Answer:

1,2 and 4

M416 would be the one I would choose for heavy.

And UZI for light option.

Answer 2

Answer:

If soldiers had the options to use different weights but the bullets used are of a fixed weight. ... So, use the law of conservation of momentum for the motions of both the gun and bullet and find the relation between the mass of the gun with its recoil velocity.