Gravity is a pair of forces of attraction between every
two objects. Period !
It doesn't matter whether they're moving together, moving apart,
moving gracefully in synchrony, or at rest. The gravitational forces
of attraction between them are always there.
Answer:
a

b

Explanation:
From the question we are told that
The initial position of the particle is 
The initial velocity of the particle is 
The acceleration is 
The time duration is 
Generally from kinematic equation

=> 
=> 
Generally from kinematic equation

Here s is the distance covered by the particle, so

=> 
Generally the final position of the particle is

=> 
=> 
Answer:
-35 m/s
Explanation:
Momentum is conserved.
Momentum before firing = momentum after firing
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂
Before the bullet is fired, the bullet and rifle have no velocity, so u₁ and u₂ are 0.
0 = m₁v₁ + m₂v₂
Given m₁ = 0.7 kg, v₁ = 350 m/s, and m₂ = 7 kg:
0 = (0.7 kg) (350 m/s) + (7 kg) v
v = -35 m/s
The rifle recoils at 35 m/s in the opposite direction.