Answer: conduction :it transfers heat between objects that are in direct contact with eachother
Answer: acceleration due to gravity of planet a would be twice that of planet b. Given that the radius are thesame.
Explanation:
Acceleration due to gravity is as a result of the gravitational force of attraction of a planet to its centre.
g = GM/r^2
Where;
g = acceleration due to gravity
G = gravitational constant
M = mass of planet
r = radius of planet
Given that the two planet have the same radius, if the mass of planet a is twice the mass of planet b the the acceleration due to gravity of planet a would be twice that of planet b, because acceleration due to gravity is directly proportional to the mass of the planet.
Answer:The mass of an object is 52 kg.
Explanation:
Gravitational force on the object ,F=510 N
Acceleration due to gravity = g = 
Mass of the object = m
Force = mass × acceleration


The mass of an object is 52 kg.
isotopes are the same element, but have different numbers of neutrons (but still have the same number of electrons and protons), hence have a different mass number.