Answer:
Hi, Since energy levels in the nucleus are much higher than those in the gas, the nucleus will cool down by emitting a more energetic electromagnetic wave called a gamma ray . Gamma ray emission causes no change in the number of particles in the nucleus meaning both the atomic number and mass number remain the same.
Answer:

Explanation:
Given that,
Pressure, P = 1 atm = 101325 Pa
Area of the square surface, A = 10² = 100 m²
We need to find the mass of vertical column of air. We know that, pressure is equal to the force acting per unit area. So,

So, the required mass of the vertical column of air is
.
Answer:
8 mph
Explanation:
4 miles in half hour so you add 4 more for the second half
Top left: slowing down
Top right: not moving
Bottom left: moving at a constant speed
Bottom right: speeding up
Answer:
a luminous ball of plasma