Answer:
30.63 m
Explanation:
Using y = ut + 1/2gt² where u = initial speed of block = 0 m/s, g = acceleration due to gravity = 9.8 m/s² and t = time of fall = 2.5 s and y = height of fall.
So, substituting the values of the variables into the equation, we have
y = ut + 1/2gt²
y = 0 m/s × 2.5 s + 1/2 × 9.8 m/s² × (2.5 s)²
y = 0 m + 4.9 m/s² × 6.25 s²
y = 0 m + 30.625 m
y = 30.625 m
y ≅ 30.63 m
So, the brick fell 30.63 m
Inertia is that quantity which depends solely upon mass. The more mass, the more inertia. Momentum is another quantity in Physics which depends on both mass and speed.
Answer:

Attractive
Explanation:
Data provided in the question
The potential energy of a pair of hydrogen atoms given by 
Based on the given information, the force that one atom exerts on the other is
Potential energy μ = 
Force exerted by one atom upon another

or

or

As we can see that the
comes in positive and constant which represents that the force is negative that means the force is attractive in nature
What that means is the atom is so radioactive that the nucleus is unstable.