Question

The distance from New York to Tokyo is approximately 10^4 km. When it is 6:00 p.m. in New York, it is 7:00 a.m. of the next day of the week in Tokyo. Use that information to do an order-of-magnitude estimate of the speed at which the earth's surface moves because of the earth's rotation.

A. ~ 10^10 km/h

B. ~ 10^8 km/h

C. ~ 10^5 km/h

D. ~ 10^3 km/h

:/ Explain please? Thank you!! :)

Answer 1

How many hours apart are the two cities?

Answer 2

ermm 13 hours? :/

Answer 3

so round that to 10 hours to make the number easier to deal with

Answer 4

divide the distance (10^4 km) by the time difference 10 hrs

Answer 5

ahh okay :)

sooo we get.... 1000?

Answer 6

which is 10^??

Answer 7

10^3 ??

so D?!! :O

Answer 8

yep and this page

http://image.gsfc.nasa.gov/poetry/ask/a10840.html

says the earth rotation speed is 1180 kilometers/hr

so pretty close to 1000 km/hr. This estimate isn't that bad.

Answer 9

oh haha that's awesome!! :D thank you so much!! :)

Answer 10

oh sry, 1670 kilometers/hour at the equator and 1180 kilometers/hr 45 degrees lattitude

still both are close to 1000

Answer 11

hahaha yeah :) woo! thanks!! :D