Answer:
The heat causes the molecules on rubbing surfaces to move faster and have more energy.
Betelgeuse is one of the largest known stars and is probably at least the size of the orbits of Mars or Jupiter around the sun. That's a diameter about 700 times the size of the Sun or 600 million miles. For a star it has a rather low surface temperature (6000 F compared to the Sun's 10,000 F).
Answer:
The gravitational force is related to the mass of each object.
The gravitational force is an attractive force.
Explanation:
Gravitational force is a long range force of attraction between any two masses.
Mathematically given as :

where:
are the masses
r= distance between the center of mass of the two objects.
G= gravitational constant = 
From the above relation of eq. (1) it is clear that,
Gravitational force is inversely proportional to the square of the distance and directly proportional to the masses.
The mass of an object is independent of its size due to the fact that density may vary for different objects.
The force of gravity varies with height as:

where:

gravity at height
of the center of mass of the object from the center of mass of the earth.
and we know that force:

where: m= mass of the object.