Answer:
The near point of an eye with power of +2 dopters, u' = - 50 cm
Given:
Power of a contact lens, P = +2.0 diopters
Solution:
To calculate the near point, we need to find the focal length of the lens which is given by:
Power, P = 
where
f = focal length
Thus
f = 
f =
= + 0.5 m
The near point of the eye is the point distant such that the image formed at this point can be seen clearly by the eye.
Now, by using lens maker formula:

where
u = object distance = 25 cm = 0.25 m = near point of a normal eye
u' = image distance
Now,



Solving the above eqn, we get:
u' = - 0.5 m = - 50 cm
The answer is B) <span>equilibrium
hope this helps!=-)</span>
Answer:
the heavier skater has less momentum
hope it is helpful to you
Answer: The wave can flip upside down.
Reflection is the bending of a wave when it cannot pass through. For example, plain mirrors which are flat, a ray of light hits the mirror and is reflected from the mirror since it cannot pass through
When reflection occurs the speed and frequency of the wave does not change but the wave is flipped upside down.
The speed does not change because speed is affected by the change in medium the frequency also remains the same since the energy of the wave does not change.