Answer to Question #169928 in Mechanics | Relativity for ella

Question

Students launch identical marbles of mass mm horizontally from a toy cannon of varying mass MC, where MC is always greater than mm, as shown above. The students can attach weights to the cannon to change MC. Each time a marble is launched, the cannon slides backward before coming to rest. The coefficient of kinetic friction between the cannon and the ground is μ (mu). For each launch, the students vary the mass of the cannon and launch a marble with the same speed v relative to the ground. The students record the distance x that the cannon slides backward.

(c) If constant horizontal forces were exerted over the same distance on the cannon and on the marble after the launch, which object would require a force with a greater magnitude to completely stop it? Without manipulating or referencing equations, briefly explain your reasoning.

Answer 1

When a marble is launched, mass of cannon is changed. If marble is launched from canon, then it will move in backward direction by the law of conservation of momentum. But there is sufficient force of friction is available which will stop the further motion of the cannon.

C) if some external force is applied on canon and marble, them marble will move large distance than canon. As force is applied in direction of launch of marble. Marble speed will increase because of force. But for canon, force is opposite to direction of motion, so it will cover less distance.