Answer: The ray that passes through the focal point on the way to the lens will refract and travel parallel to the principal axis. ... All three rays should intersect at exactly the same point.
Explanation: Once these incident rays strike the lens, refract them according to the three rules of refraction for converging lenses.
The angular acceleration of a rotating object is given by

where

is the final angular speed of the object

is its initial angular speed

is the time taken to accelerate
For the wheel in our problem,

,

and

, so its angular acceleration is
Answer:
The handrails must be approximately 10.63 meters long
Explanation:
The given parameters are;
The height of the bleachers, h = 8 m
The depth of the bleachers, d = 7 m
The length of the hand rails to go along the bleachers from bottom to top is given by Pythagoras' Theorem as follows;
The length of the hand rail = √(d² + h²)
∴ The length of the hand rail = √(7² + 8²) = √113 ≈ 10.63
In order for the handrails to go along the bleachers from top to bottom, they must be approximately 10.63 meters long.