Answer:
20 J
Explanation:
Kinetic energy is given as half of the product of mass and the square of velocity of an object:
KE = 
where m = mass = 40 kg
v = velocity = 1 m/s
Hence, Mary's kinetic energy is:
KE = 
KE = 20 * 1 = 20 J
She has a kinetic energy of 20 J.
10,000 units of momentum.
p=mv
20,000=m(2v)
10,000=mv
Explanation:
It is given that,
When a high-energy proton or pion traveling near the speed of light collides with a nucleus, 
Speed of light, 
Let t is the time interval required for the strong interaction to occur. The speed is given by :




So, the time interval required for the strong interaction to occur is
. Hence, this is the required solution.
The answer for this question is Control Variable because it doesn’t change throughout the experiment.
Active Optics.
Hope that helps, Good luck! (: