1. Intro to Physics Units

Express the following angles in radians: 45.0°. Give as numerical values and as fractions of π.

The platter of the hard drive of a computer rotates at 7200 rpm (rpm = revolutions per minute = rev/min). What is the angular velocity (rad/s) of the platter?

(II) An average active person consumes about 2500 Cal a day. (a) What is this in joules? (b) What is this in kilowatt-hours? (c) If your power company charges about per kilowatt-hour, how much would your energy cost per day if you bought it from the power company? Could you feed yourself on this much money per day?

Determine the conversion factor between km/h and m/s.

How many years are there in 1.00 second?

What is the conversion factor between ft² and yd²

A light-year is the distance light travels in one year (at speed = 2.998 x 10⁸ m/s). How many meters are there in 1.00 light-year?

How much longer (percentage) is a one-mile race than a 1500-m race ('the metric mile')?

A passenger jet uses about 12 liters of fuel per km of flight. What is that value expressed as miles per gallon?

American football uses a field that is 100.0 yd long, whereas a soccer field is 100.0 m long. Which field is longer, and by how much (give yards, meters, and percent)?

Computer chips (Fig. 1–15) can be etched on circular silicon wafers of thickness 0.300 mm that are sliced from a solid cylindrical silicon crystal of length 25 cm. If each wafer can hold 750 chips, what is the maximum number of chips that can be produced from one entire cylinder?

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An angstrom (symbol Å) is a unit of length, defined as 10^-10, which is on the order of the diameter of an atom. How many nanometers are in 1.0 angstrom?