Answer:
The energy level is 5.
Explanation:
Given that,
n = 3
l = 2
We know that,
l shows the number of sub-shells and define the number of angular nodes.
n shows the number of electron shell.
is a quantum number. It is define the number of energy level in a sub-shells .
is define the spin of the electron.
So, The quantum number is
is 
and 
for every energy level.
The energy level is 5.
Hence, The energy level is 5.
Answer:
E = 16.464 J
Explanation:
Given that,
Mass of tetherball, m = 0.8 kg
It is hit by a child and rises 2.1 m above the ground, h = 21. m
We need to find the maximum gravitational potential energy of the ball. The formula for the gravitational potential energy is given by :
E = mgh
g is acceleration due to gravity
E = 0.8 kg × 9.8 m/s² × 2.1 m
= 16.464 J
So, the maximum potential energy of the ball is 16.464 J.
Answer:
That is, mechanical waves cannot travel through a vacuum. This feature of mechanical waves is often demonstrated in a Physics class. A ringing bell is placed in a jar and air inside the jar is evacuated. Once air is removed from the jar, the sound of the ringing bell can no longer be heard.
