Because Mars is too far away for its gravitational pull to affect us, in addition Earths gravitational pull is greater than Mars anyways.
Answer:

Explanation:
As we know that train is initially moving with the speed

now we know that

now the final speed of the train when it crossed the crossing


now we can use kinematics here



Now the time to cross that junction is given as



In collision that are categorized as elastic, the total kinetic energy of the system is preserved such that,
KE1 = KE2
The kinetic energy of the system before the collision is solved below.
KE1 = (0.5)(25)(20)² + (0.5)(10g)(15)²
KE1 = 6125 g cm²/s²
This value should also be equal to KE2, which can be calculated using the conditions after the collision.
KE2 = 6125 g cm²/s² = (0.5)(10)(22.1)² + (0.5)(25)(x²)
The value of x from the equation is 17.16 cm/s.
Hence, the answer is 17.16 cm/s.
Beginning around 5,500 years ago, the Sumerians built cities along the rivers in Lower Mesopotamia, specialized, cooperated, and made many advances in technology. The wheel, plow, and writing (a system which we call cuneiform) are examples of their achievements.