Discuss the below in detail:
Q1. 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.
Q2. It has been estimated that the Earth contains 109 metric tons of natural uranium that can be mined economically. Of this total, 0.7% is 235U that can be fissioned to produce energy. Assume 208 MeV per fission; 1 MeV = 1.6x10-13 J; 235 g of U has 6x1023 atoms.
a. How many atoms of 235U are there in 109 metric tons of natural uranium?
b. What is the energy release possible from the 235U in 109 metric tons of natural uranium?
c. If all the world's current power needs (7x1012 W) were supplied by 235U fission, how long would this supply of uranium last?
Q3. The first atomic bomb released energy equivalent to 20 kilotons of TNT. If 1 ton of TNT releases 4x109 J, how much uranium was consumed through fission in the bomb? Assume 208 MeV per fission; 1 MeV = 1.6x10-13 J; 235 g of U has 6x1023 atoms. Hint: use the energy released and the energy per unit mass of uranium.
Q4. 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 near sighted and farsighted mean, and how glasses correct the condition.
Q5. Why?
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?