SPEED!

 

Work the following problems using the basic concepts: 

rate = amount/time                                speed = distance/time

 

The following information may be helpful – watch your units of measure!

            1 mile @ 1609 m                                   1 hour = 3600 s           

speed of light = 3.00 x 108 m/s              speed of sound = 343 m/s

 

 

1.      Suppose you drive 110 miles in 1.3 hours.  Determine your speed in mph.

2.      Mr. M drives about 20 miles in about 25 minutes every morning during his daily commute to FHS.  What is his average speed in miles per hour?

3.      How far does sound travel in 1.0 minute?  How far does light travel in 1.0 minute?

4.      It takes light 5.4 hours to travel from the Sun to Pluto.  What distance is this?

5.      Radio waves travel through space at the speed of light.  Scientists have sent radio waves from Earth to Venus and then measured the return of the same radio waves to Earth (after “bouncing” off of Venus).  Suppose the amount of time for the radio waves to go to Venus and back to Earth is 5 minutes and 40 seconds.  Determine the distance from Earth to Venus.

6.      Suppose you plan a trip to Nashville, which is 180 miles.  If you drive at a speed of 75 mph how many minutes will the trip take?

7.      Determine the amount of time for sound to travel a distance of 5.00 miles.  Determine the amount of time for light to travel a distance of 5.00 miles.

8.      Suppose you start counting out loud at a rate of 1.5 numbers per second.  (a) If you count at this same rate for 1.00 minute what number will you reach?  (b) At the same rate, how much time will it take to count from 1 to 1000?  (c) At the same rate, how much time will it take to count from 1 to 1,000,000 (a million)? (d) At the same rate, how much time will it take to count from 1 to 1,000,000,000 (a billion)?

Note:  For parts b, c, and d convert your answers to the most appropriate unit of time: minutes, hours, days, etc.

9.      At the same speed at which it orbits the Earth, 7600 m/s, how much time would it take the space shuttle to travel to the nearest star, Proxima Centauri, which is located 4.0 x 1016 m away?  Again choose an appropriate unit of time for your answer.

 

Answers

1.      85 mph

2.      48 mph

3.      21 km, 18 Gm

4.      5.8 × 1012 m

5.      51 Gm

6.      144 min

7.      23.5 s, 2.68 × 10-5 s

8.      a. 90
b. 11.1 min
c. 7.72 days
d. 21.1 years

9.      167000 years