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
Answer:
2000metres
Explanation:
Pressure= density x height x gravity
Gravity is always a constant = 10N/kg
so height= Pressure/( density x gravity)
h= 20000000/(1000 x10)
h= 2000 metres
Both have positive charge. In fact, an alpha particle IS a nucleus of a Helium atom.
The angle between the two vectors is 0⁰, thus the two vectors are parallel to each other.
<h3>Angle between the vectors</h3>
The angle between the vectors describes the direction of the vector and the value of the angle can be determined from the horizontal and vertical components of the vectors as shown below.
The sum of the horizontal components and vertical components of the vectors is calculated as follows;
Sum of the horizontal component of the vectors, x = 1 + 1 = 2
Sum of the vertical component of the vectors, y = -1 + 1 = 0
The angle between the vectors is calculated as follows;
θ = arc tan (y/x)
θ = arc tan (0/2)
θ = arc tan (0)
θ = 0⁰
The angle between the two vectors is 0⁰, thus the two vectors are parallel to each other.
Learn more about vectors here: brainly.com/question/25811261
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