Suppose you are still a two-dimensional being, living on the same sphere of radius R. Show that if you draw a circle of radius r, the circle’s circumference will be C= 2(pi)Rsin(r/R) (3.62) Idealize the Earth as a perfect sphere of radius R = 6371 km. If you could measure distances with an error of ± 1 meter, how large a circle would you have to draw on the Earth’s surface to convince yourself that the Earth is spherical rather than flat?

Ryden, Barbara. Introduction to Cosmology (pp. 47-48). Cambridge University Press. Kindle Edition.

pe = weightxheight = 2000x1000=2,000,000joules

beta is electron from nucleus

something from nucleus has changed, but charge must be same for cons of charge

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.