Answer:
1. 
2. 
Explanation:
1. According to Newton's law of motion, the puck motion is affected by the acceleration, which is generated by the push force F.
In Newton's 2nd law: F = ma
where m is the mass of the object and a is the resulted acceleration. So in the 2nd experiment, if we double the mass, a would be reduced by half.

Since the puck start from rest, in the 1st experiment, to achieve speed of v it would take t time

Now that acceleration is halved:


You would need to push for twice amount of time 
2. The distance traveled by the puck is as the following equation:

So if the acceleration is halved while maintaining the same d:

As
, then
. Also 



So t increased by 1.14
Answer:
Atoms are single neutral particles.
example: Ne, O
Molecules are neutral particles made of two or more atoms bonded together.
example:O2,HCl
Answer:
The proton has much greater mass
Explanation:
- Protons and electrons are part of an atom
- Proton exists inside nucleus whereas electron keep moving around the nucleus
- Electrons have negative charge where as protons have positive charge .
Answer: The force does not change.
Explanation:
The force between two charges q₁ and q₂ is:
F = k*(q₁*q₂)/r^2
where:
k is a constant.
r is the distance between the charges.
Now, if we increase the charge of each particle two times, then the new charges will be: 2*q₁ and 2*q₂.
If we also increase the distance between the charges two times, the new distance will be 2*r
Then the new force between them is:
F = k*(2*q₁*2*q₂)/(2*r)^2 = k*(4*q₁*q₂)/(4*r^2) = (4/4)*k*(q₁*q₂)/r^2 = k*(q₁*q₂)/r^2
This is exactly the same as we had at the beginning, then we can conclude that if we increase each of the charges two times and the distance between the charges two times, the force between the charges does not change.