Answer:
first law: an object remains in uniform motion except an external force has acted upon it eg a ball in stable motion doesn't move until one moves or kicks it
second law:the body acted upon by an external force gains a momentum which is directly proportional to the applied force and acts in the direction of the force
third law: to every action there is an equal and opposite reaction eg if u push someone the person moves backward away from you and not towards you
This link should help you out!!
http://mszopiak.weebly.com/uploads/5/5/8/1/55815541/p_vtgraphskey_mszopiak.pdf
Answer:
(c) 10.29 J
(d) 113.19 J
(e) 113.19 J
(f) 10061 N/m
Explanation:
15 cm = 0.15 m
Let g = 9.8 m/s2
(c) The work done by gravitational force is the product of gravity force and the distance compressed

(d) By using law of energy conservation with potential energy reference being 0 at the maximum compression point. As the ball falls and come to a stop at the compression point, its potential energy is transferred to elastic energy, which is the work that the mattress does on the ball:


where h = 1.5 + 0.15 = 1.65 m is the vertical distance that it falls.

(e) Before the compression, the potential energy of the mattress is 0. After the compression, the potential energy is 113.19J. So it has increased by 113.19J due to the potential energy transferred from the falling ball.
(f) 


Answer:
air or vacuum is the least refractive index medium of most rare medium
all other medium has more value of refractive index and hence the speed will be less than the speed of the air
Explanation:
As we know that speed of light in any medium and speed of light in air is related to each other by the equation

here we know that

[tex]\mu [tex] = refractive index of the medium
so we know that air or vacuum is the least refractive index medium of most rare medium
all other medium has more value of refractive index and hence the speed will be less than the speed of the air
In summer because the air in summer is less dense.