The force of gravitation between two objects is directly proportional to the product of masses of two bodies and inversely proportional to the square of distance between them. So, the force on earth due to the satellite and the force on satellite due to the earth is same in magnitude.
mass number is now 4 times less than the original value so alpha decay occur during alpha decay the mass number is decreased 4 times and atomic number decreased 2 times than the original value
