Answer:
a)1.51*10^-22joules b) 1.89*10^-7m
Explanation:
Work done to stop the proton = the kinetic energy of the proton = 1/2 mv^2 = 1/2* 1.67*10^-27* 425*425 = 1.51* 10 ^ -22 joules
b) net force acting to stop the proton = 8.01*10^-16
Work done needed to stop the proton = net force acting opposite the motion * distance
Distance covered = need work done/ net force
Distance = 1.51*10^-22/8.01*10^-16= 1.89*10^-7m
Answer: 3. F1 = F2
Explanation:
According to <u>Newton's law of Gravitation</u>, the force 
exerted <u>between two bodies</u> or objects of masses 
and 
and separated by a distance 
is equal to the product of their masses divided by the square of the distance:
(1)
Where 
is the gravitational constant
Now, in the especific case of the Earth and the satellite, where the Earth has a mass and satellite a mass , being both separated a distance , the force exerted by the Earth on the satellite is:
(2)
And the force exerted by the satellite on the Earth is:
(3)
As we can see equations (2) and (3) are equal, hence the magnitude of the gravitational force is the same for both:
True, They contain old stars and posses little gas or dust
