Answer:
d. Two soccer balls that are touching each other
Explanation:
Let 
be the mass of a tennis ball, 
is the mass of a soccer ball.
As the mass of a soccer ball is more than the mass of a tennis ball, so
Let 
be the distance between the centers of both the balls near each other and 
be the distance between the centers of both the balls touching each other.
So, 
The gravitational force, F, between the two objects having masses M and m and separated by distance d is
Where G is the universal gravitational constant.
As, the gravitational force is directly proportional to the product of both the masses and inversely proportional to the square of the distance between them, so selecting the larger mass (, soccer ball) separated by a lesser distance (, touching) to get more gravitational force.
Therefore, there will be a larger gravitational force between them when two soccer balls touching each other.
Hence, option (d) is correct.
Answer:
The Gravitational potential energy at large distances is directly proportional to the masses and inversely proportional to the distance between them. The gravitational potential energy increases as r increases.
Examples of Gravitational Energy
A raised weight.
Water that is behind a dam.
A car that is parked at the top of a hill.
A yoyo before it is released.
Carbon-14 atom have 6 protons plus 8 neutrons.
Explanation
Carbon-12 and Carbon-14 are examples of isotopes of carbon that have huge applications in the field of science.
Isotopes are those elements who have equal number of protons and electrons whereas their neutrons differ.
Therefore isotopes have same atomic number, as atomic number depends on number of protons or number of electrons whereas number of neutrons do not have a role in atomic number.
But mass numbers of isotopes are different as mass numbers depend on the number of protons and number of electrons.
To find instantaneous velocity given a position vs. time graph is find the derivative at that given point. In other words, find the slope at that point.
So at t = 1s, the velocity is 5/2 m/s.
Hope this helps!
