Stars are born when ……….contract due to the pull of gravity.
a) solid
b) liquid
c) gaseous cloud
d) plasma
As the particles of gaseous cloud of stars merge, their kinetic energy increases, which of the following reaction is started?
a) chemical
b) physical
c) nuclear
d) biological
Explanation:In nuclear physics and nuclear chemistry, a nuclear reaction is a process in which two nuclei, or a nucleus and an external subatomic particle, collide to produce one or more new nuclides. Thus, a nuclear reaction must cause a transformation of at least one nuclide to another.
Which of the following reactions change light elements into heavier ones and release energy in the process and stars appear to glow?
a) chemical
b) physical
c) nuclear
d) biological
In stars like our sun, which of the following is released in huge amount by the nuclear reactions?
a) mass
b) matter
c) energy
d) none of these
How much time has taken by sun to contract and reach stability?
a) 30 thousand years
b) 30 million years
c) 30 billion years
d) 30 trillion years
For how much expected time, the sun will remain stable since its birth?
a) 10 thousand years
b) 10 million years
c) 10 billion years
d) 10 trillion years
