Stars<span> are powered by </span>nuclear fusion<span> in their cores, mostly converting hydrogen into helium. The production of new elements via </span>nuclear<span> reactions is called nucleosynthesis. A </span>star's<span> mass determines what other type of nucleosynthesis </span>occurs<span> in its core (or during explosive changes in its life cycle). READ THIS AND YOU WILL UNDERSTAND I THINK IS TRUE </span>
Answer:

Explanation:
The energy of a photon is given by:

where
h is the Planck constant
c is the speed of light
is the wavelength of the photon
In this problem, we have a microwave photon with wavelength

Substituting into the equation, we find its energy:

Answer : The correct option is, (c) 
Explanation :
First we have to calculate the energy or heat.
Formula used :

where,
E = energy (in joules)
V = voltage (in volt)
I = current (in ampere)
t = time (in seconds)
Now put all the given values in the above formula, we get:


Now we have to calculate the heat capacity of the calorimeter.
Formula used :

where,
C = heat capacity of the calorimeter
= initial temperature = 
= final temperature = 
Now put all the given values in this formula, we get:


Therefore, the heat capacity of the calorimeter is, 
Nuclear fusion reactions convert protons into helium; thus, becoming the source of all energy radiated by the sun.
Answer: Option D
<u>Explanation:</u>
Nuclear fusion reaction is one among the two nuclear reactions in which the atoms nucleus interact with each other to produce the products. In nuclear fusion, two smaller atoms react together to form a new atom with bigger size.
So large amount of energy is required to start the nuclear fusion reaction. The fusion reactions mostly occurs in stars. The illumination in Stars even the Sun is due to nuclear fusion reaction occurring with the atoms present in them.
Mostly the energy radiated by Sun is due to the protons-protons chain reaction. In this chain reaction, the protons get converted into helium due to nuclear fusion reaction, thus becoming the source of all energy radiated by the Sun.