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:


All of the above is right
Answer:
Explanation:
Inital KE = (1/2) m v^2 = (1/2) * 1500 * 50^2 = 1,875,000 J
Final KE = (1/2) * 1500 * 100^2 = 7,500,000 J
But ,
4 * 1875000 = 7500000
so the KE has increased by 4 times.
Answer:
check image
Explanation:
For any question related to newons law of motion first draw the free body diagram(FBD),
When light is passing from a denser medium to a lighter medium ( for example: from water to air)
<span> When the angle of refraction is greater than the critical angle( angle of incidence when the angle of refraction is perpendicular to the normal) of the denser medium.</span>