Answer:
mass.
Explanation:
other physical factors are changeable but the mass of a particular substance is always constant.
A pulley is another sort of basic machine in the lever family. We may have utilized a pulley to lift things, for example, a banner on a flagpole.
<u>Explanation:</u>
The point in a fixed pulley resembles the support of a lever. The remainder of the pulley behaves like the fixed arm of a first-class lever, since it rotates around a point. The distance from the fulcrum is the equivalent on the two sides of a fixed pulley. A fixed pulley has a mechanical advantage of one. Hence, a fixed pulley doesn't increase the force.
It essentially alters the direction of the force. A moveable pulley or a mix of pulleys can deliver a mechanical advantage of more than one. Moveable pulleys are appended to the item being moved. Fixed and moveable pulleys can be consolidated into a solitary unit to create a greater mechanical advantage.
Answer: 0.2m
Explanation: Firstly only the Rocket's Weight Compress the spring which can be found by

According to Hooks Law

The part b and c of this question is done in the attachment
Answer:
the total momentum is 8 .2 kg m/s in north direction.
Explanation:
given,
mass(m₁) 3.00 kg, moving north at v₁ = 3.00 m/s
mass(m₂) 4.00 kg, moving south at v₂ = 3.70 m/s
mass(m₃) 7.00 kg, moving north at v₃ = 2.00 m/s
north as the positive axis
south as the negative axis
now
total momentum = m₁v₁ + m₂ v₂ + m₃ v₃
total momentum = 3 x 3 - 4 x 3.7 + 7 x 2
= 9 - 14.8 + 14
= 8 .2 kg m/s
hence, the total momentum is 8 .2 kg m/s in north direction.