The velocity of the submarine immediately after firing the missile is 0.0104 m/s
Explanation:
Mass of the submarine M=50 tonne=
Mass of the missile m=40 kg
velocity of the missile v= 13m/s
we have to calculate the velocity of the submarine after firing
This is the recoil velocity and its expression is derived from the law of conservation of momentum
recoil velocity of the submarine

Kepler's 3rd law is given as
P² = kA³
where
P = period, days
A = semimajor axis, AU
k = constant
Given:
P = 687 days
A = 1.52 AU
Therefore
k = P²/A³ = 687²/1.52³ = 1.3439 x 10⁵ days²/AU³
Answer: 1.3439 x 10⁵ (days²/AU³)
- Gravitational force depends only on mass and distance, not on the state of matter.
- The forces of attraction between molecules in matter are electromagnetic in nature, not gravitational.
- These attractive forces are stronger in a solid than in a liquid than in a gas.
- Gravitational forces between molecules is completely negligible compared to the em forces.
So, key answer is inter-molecular forces of solids is stronger than liquids.
There is no <span>radioactive decay</span>