Answer: m = 0.035kg = 35g
Explanation: Momentum p=0.140kgm/s
Velocity v=4m/s
Mass m=?
Formula-
Momentum depends on the mass of the object in motion and its velocity.
The equation for momentum is
p = mv
m = p/v
m = 0.140/4
m = 0.035kg
m = 35g
Hence, in the toy dart gun mass of the dart is 0.035kg.
The Potential energy stored in the system is 1 J
<u>Explanation:</u>
Given-
Mass, m = 4 kg
Spring constant, k = 800 N/m
Distance, x = 5cm = 0.05m
Potential energy, U = ?
We know,
Change in potential energy is equal to the work done.
So,

By plugging in the values we get,

Therefore, Potential energy stored in the system is 1 J
Answer:
Due to Conservation of Energy just as the ball hits the ground it's potential energy is assumed zero
Therefore disregarding air resistance all energy is converted into potential energy.
So KE = PE
(5 J)
The molarity remains the same so the ratio does not change