Answer:
Because they are both easy to measure (?)
Explanation:
(I'm not really sure, there are no choices. If there were different options I might be able to better answer this)
The correct answer is:

Let's see why.
1 amu corresponds to the mass of the proton, which is:

if we convert this into energy, using Einstein equivalence between mass and energy, we find:

Now we can convert it into electronvolts:

So, 1 amu = 934 MeV. Therefore, 3 amu corresponds to 3 times this value:
Answer:
40,000
Explanation:
Momentum is defined as mass*velocity, so a doubling of velocity means a doubling of momentum
Answer
given,
D = 50 mm = 0.05 m
d = 10 mm = 0.01 m
Force to compress the spring




F = 3160 N
stress correction factor from stress correction curve is equal to 1.1
now, calculation of corrected stress


= 442.6 Mpa
The tensile strength of the steel material of ASTM A229 is equal to 1300 Mpa
now,



since corrected stress is less than the
hence, spring will return to its original shape.