Answer:
The magnification is 
Explanation:
From the question we are told that
The power of the lens is 
Generally 
The object distance is
the negative sign is because the distance is measured in the opposite direction of incident light (i.e away )
Generally the focal length is mathematically represented as
=>
=> 
converting to cm
=> 
Generally from lens equation we have that

=> 
=> 
Generally the magnification is mathematically represented as

=> 
=> 
Answer:
When argon changes from a gas to a liquid, the forces between the molecules become stronger so the particles become closer together and come into come into contact more often. The particles move at a less faster rate as the have less kinetic energy due to decrease in temperature. When argon changes from a liquid to a solid, the forces become even stronger so the particles are arranged in fixed positions and vibrate around a fixed point as they cannot move past each other
Answer:
44 N
Explanation:
The electrostatic forces between two charges is given by:

where
k is the Coulomb's constant
q1 and q2 are the two charges
r is their separation
We notice that the force is directly proportional to the charges.
In this problem, initially we have a force of
F = 22 N
on a q2 = 4.0 C, exerted by a charge q1.
If the charge is doubled,
q2 = 8.0 C
This means that the force will also double, so it will be

If F =m*a
and the question says how much force the s needed to accelerate a 68kg skier to a rate of 1.2ms^-2
Then F = 68*1.2
The statement is false. Balanced forces can NOT change the speed OR direction of an object's motion. (See Newton's #1 law of motion.)