Presentation on theme: "PHYSICS 218 (517-520) recitation 1 In recitation, –We shall discuss exercises and problems. They may include homework problems. –Quiz: you are supposed."— Presentation transcript:
PHYSICS 218 ( ) recitation 1 In recitation, –We shall discuss exercises and problems. They may include homework problems. –Quiz: you are supposed to solve a quiz at each recitation. –Make a group so that each group contains 3 (or 4) students. Take a seat as in your Lab. –You should collaborate with your partners to solve quiz problems. You work as teams on the quiz problem. One group has one answer paper. The answer paper should have names and UIN of all group members. The group members will have the same credit for recitation quiz. One of you may serve as a focused peer mentor. There is no Lab today (Sep.1). There is no quiz today (Sep.1).
Unit –An equation must always be dimensionally consistent. –You cannot add length and time. Unit conversion Eg. The official world land speed record is km/h. Express this speed in m/s. =1 Unites are treated just like algebraic symbols. DO NOT forget to give your answers with correct units.
Ex. The inhabitants of a small island begin exporting beautiful cloth made from a rare plant that grows only on their island. Seeing how popular the small quantity that they export has been, they steadily raise their prices. A clothing maker from New York, thinking that he can save money by "cutting out the middleman," decides to travel to the small island and buy the cloth himself. Ignorant of the local custom of offering strangers outrageous prices and then negotiating down, the clothing maker accepts (much to everyone's surprise) the initial price of 400 tepizes/m 2. The price of this cloth in New York is 120 dollars/yard 2. If he bought 500 m 2 of this fabric, how much money did he lose? (1 tepiz = dollar and 1 yard = m.) Strategy How much money he spent? How much he would spent in NY?
Problem 1.67(a) Approximately how many atoms make up our planet? For simplicity, assume the average atomic mass of the atoms is 14 g/mol. Avogadro's number gives the number of atoms in a mole.
x y is defined from the positive x-axis to the direction of a vector toward the positive y- axis, i.e., counterclockwise. arctan function has two solutions in the range of (0, 2 ). y