## Phys 100: Problem Set Week 1

Giancoli Chapters 1 (Measurement and Estimating) and 2 (Describing motion in one dimension) and, with more on inertial reference frames, pages 74 and 726-729

### Problems:

This will be shorter than usual since we have a short week before Wednesday.

(1) Ch 1 Problem 3: Write the following in powers of ten notation (a) 1.156 (b) 21.8 (c) 0.0068 (d) 27.635 (e) 0.219 (f) 444.

(2) Ch 1 Problem 34: GPS satellites can be used to determine positions with great accuracy. The system works by determining the distance between the observer and several satellites. If one satellite is at a distance of 20,000 km for you, what percent accuracy in the distance is required if you desire a 2 meter uncertainty? How many significant figures do you need in the distance?

(3) Ch 1 Problem 45 Good to do on an evening this weekend! Feel free to use your thumb instead of a pencil: Hold a pencil in front of your eye at a position that just blocks out the Moon. Make appropriate measurements to estimate the diameter of the moon, given an Earth-Moon distance of 3.8 * 10^5 km.

(4) Estimate the number of library books in Burke.

(5) Ch 2 Question (not Problem) 16: In a lecture demonstration a 3.0 m long vertical string with ten bolts tied to it at equal intervals is dropped. The string falls on a tin plate, and the class hears a "clink" each time a bolt lands on the plate. The sounds will not occur at equal time intervals. Why? Will the time between clinks increase or decrease near the end of the fall? How could the bolts be tied so that the clinks occur at equal intervals?