Vectors need direction and magnitude to exist, otherwise, it becomes scalars that do not require direction to be expressed.
eg - Velocity is a vector as it needs direction, but speed is scalar and does not need direction
hope this helps
Answer:

(we need the mass of the astronaut A)
Explanation:
We can solve this by using the conservation law of the linear momentum P. First we need to represent every mass as a particle. Also we can simplify this system of particles by considering only the astronaut A with an initial speed
of 0 m/s and a mass
and the IMAX camera with an initial speed
of 7.5 m/s and a mass
of 15.0 kg.
The law of conservation says that the linear momentum P (the sum of the products between all masses and its speeds) is constant in time. The equation for this is:

By the law of conservation we know that
For
(final linear momentum) we need to treat the collision as a plastic one (the two particles stick together after the encounter).
So:


You can accelerate by changing direction, even though you don't speed up/down. Remember that acceleration is a vector so, it has a direction and a magnitude. That's why this works! Hope it helps.
Electrons is transferred in order for static electricity to occur.