Answer:
Velocity of the electron at the centre of the ring, 
Explanation:
<u>Given:</u>
- Linear charge density of the ring=
- Radius of the ring R=0.2 m
- Distance of point from the centre of the ring=x=0.2 m
Total charge of the ring
Potential due the ring at a distance x from the centre of the rings is given by
The potential difference when the electron moves from x=0.2 m to the centre of the ring is given by
Let
be the change in potential Energy given by
Change in Potential Energy of the electron will be equal to the change in kinetic Energy of the electron
So the electron will be moving with
An excited atom can return to its ground state by absorbing electromagnetic radiation is false about the electromagnetic radiation.
Option B
<u>Explanation</u>:
In the scope of modern quantum theory, the term Electromagnetic radiation is identified as the movement of photons through space. Almost all the sources of energy that we utilize today such as coal, oil, etc are a product of electromagnetic radiation which was absorbed from the sun millions of years ago.
Various properties of electromagnetic radiations are a directly proportional relationship between the energy and the frequency, Inverse proportionality between frequency and the wavelength, etc. Hence, we can conclude that an "excited atom" can never return to its ground state by assimilating electromagnetic radiation and the 2nd statement is false.
3.6 kg.
<h3>Explanation</h3>
How much heat does the hot steel tool release?
This value is the same as the amount of heat that the 15 liters of water has absorbed.
Temperature change of water:
.
Volume of water:
.
Mass of water:
.
Amount of heat that the 15 L water absorbed:
.
What's the mass of the hot steel tool?
The specific heat of carbon steel is 
.
The amount of heat that the tool has lost is the same as the amount of heat the 15 L of water absorbed. In other words,
.
.
.
Force bc it says the ability to make stuff happen
