Scientific Notation

Pre-Test Answers

1. Classify the following as a unit of "length," "time," or "mass."

   1. second -- TIME

   2. kilogram -- MASS

   3. millimeter -- LENGTH

   4. mile -- LENGTH

2. You are given the following information:

   1 foot = 12 inches	1 yard = 3 feet
   1 meter = 1.0936 yards	1 kilometer = 1000 meters
   1 meter = 100 centimeters	1 kilometer = 0.6214 miles

   1. How many yards are in a kilometer?
      
      1 kilometer X (1000 meters / kilometer) = 1000 meters
      1000 meters X (1.0936 yards / 1 meter) = 1,093.6 yards

   2. How many centimeters in a foot?
      
      1 foot X (1 yard / 3 feet) = 0.3333 yards
      0.3333 yards X (1 meter / 1.0936 yards) = 0.3048 meters
      0.3048 meters X (100 centimeters / 1 meter) = 30.48 centimeters

   3. How many centimeters in a kilometer?
      
      1 kilometer X (1000 meters / kilometer) X (100 centimeters / meter) = 100,000 cm

   4. How many meters in a mile?
      
      1 mile X (1 kilometer / 0.6214 miles) X (1000 meters / kilometer) = 1609.3 meters

   5. How many inches in a mile?
      
      1 mile X (1 kilometer / 0.6214 miles) X (1000 meters / kilometer) = 1609.3 meters
      1609.3 meters X (1.0936 yards / meter) X (3 ft / 1 yd) = 5280 feet
      5280 feet X (12 inches / foot) = 63,357 inches

3. The formula for velocity is given as velocity = distance /time. If the units of distance are meters, and the units of time are seconds, what is the unit of velocity? meters per second, or m/s

4. The basic unit of force is the newton, and the basic formula for force is F = m X a, where m is the mass, measured in kilograms, and a is the acceleration, measured in meters / (second)². What is a newton, expressed in basic units of length, mass, and time? 1 N = 1 kg m /s²

5. For the pairs below, pick the larger unit.

   1. centimeter and meter -- meter

   2. gram and kilogram -- kilogram

   3. liter and milliliter -- liter

   4. watts and Gigawatts -- Gigawatt

6. Solve the following:

   1. How many Hertz are in 989 Megahertz? 989 X 1,000,000 Hz = 989,000,000 Hz

   2. How many meters are in 12,659 millimeters?
      12,659 mm X (1m / 1000 mm) = 1.2659 m.

   3. How many grams are in 22 kilograms? 22 kilograms X (1000 gm/kg) = 22,000 gm

   4. How many feet per second in 200 miles/hour? (Hint: There are 5280 feet in a mile, and 3600 seconds in an hour.)
      200 miles /hour X (5280 feet / mile) X (1 hour / 3600 seconds) = 293.33 ft / sec

   5. The formula for the volume of a cube is volume = length X width X height. If a box is 10 centimeters wide, 50 centmeters long, and 20 centimeters high, what is the volume of that box? Be sure to give the proper units!
      
      Volume = length X width X height = (50 cm) X (10 cm) X (20 cm) = 10000 cm³

If you missed more than one of these questions, you will probably want to start the tutorial. Remember to got throught the various parts in order, step-by-step. If you did very well on this test and don't feel you need to look at the tutorial, you might want to take the post-test to be sure you've mastered the material.