Great question !
The rate at which an object covers distance, without worrying
about the direction it's moving, is the object's SPEED .
When the direction is also given, then you have the object's VELOCITY.
This question is important. It gives us a chance to point out that
"velocity" is not just a fancy word for speed that you use when you
want to sound smart. There's actually an important difference between
'speed' and 'velocity'.
Answer:
The value of spring constant is 266.01 
Explanation:
Given:
Mass of pellet
kg
Height difference of pellet rise
m
Spring compression
m
From energy conservation law,
Spring potential energy is stored into potential energy,

Where
spring constant, 



Therefore, the value of spring constant is 266.01 
Answer:
density of the ball is 3.33 g/cc
Explanation:
As we know that the density is the ratio of mass and volume
here we know that
mass = 20 g
volume = 6 cubic cm
so we will have



Answer:
4800N
Explanation:
Lets assume,
Mass of first object = m₁
Mass of second object = m₂
Distance between the two objects = r
Thus the force between the two objects will be

where, G = Universal gravitational constant
Given, F = 2400N
New mass of second object = 2m₂
Now, the force will be




Thus, F₂ = 4800N