A convex lens is placed on a flat glass plate and illuminated from above with monochromatic red light. When viewed from above, concentric bands of red and dark are observed. What does one observe at the exact center of the lens where the lens and the glass plate are in direct contact?
a. a bright spot that is some color other than red
b. a dark spot
c. a bright red spot
d. a rainbow of color
This is an example of newtons rings. The circular interference fringes appear, associated with the variable thickness air film between the lens and the plate. ...
This solution is provided in 130 words. It discusses Newton's rings and calculates maximum intensity to solve the problem.
Church, Galileo, Uranium, Fission, Nearsighted and farsighted
1. In 1610, the Church started its attack on Galileo. They stated:
i) Suppose a cannon be fired, first due east, then due west. In one case the shot has the velocity of the earth as well as that of the force of the powder, in the other case only the difference of the two. But, in fact, no such difference is noted, and therefore the earth does not move.
ii) If the earth rotates as fast as Copernicus says, birds could not keep up with it!
Briefly, use physics to answer these two charges.
2. Please see the attachment.
3. Please see the attachment.
4. You were stranded on a desert island with John, who wears glasses. He manages to start a fire. Is John nearsighted or farsighted? Explain how you know. Explain what nearsighted and farsighted mean, and how glasses correct the condition.
5. Give brief answers to following questions.
a. Why is the sky blue?
b. Why are clouds white?
c. Why is the sunset red?
d. If you are looking at a rainbow, where is the sun and why?