Oscar learns that a point at Earth's equator travels a distance equal to Earth's circumference once every 24 hours. He wants to estimate know how fast a person standing at the equator travels as the planet rotates.

Oscar looks online and finds that the diameter of Earth is 7,911.5 miles, and that Earth rotates at a speed of 1,518 feet per second.

Using this information, how fast does a person standing still travel as Earth rotates, in miles per hour? Round your answer to the nearest whole number.

Question

Oscar learns that a point at Earth's equator travels a distance equal to Earth's circumference once every 24 hours. He wants to estimate know how fast a person standing at the equator travels as the planet rotates.

Oscar looks online and finds that the diameter of Earth is 7,911.5 miles, and that Earth rotates at a speed of 1,518 feet per second.

Using this information, how fast does a person standing still travel as Earth rotates, in miles per hour? Round your answer to the nearest whole number.

anonymous · Answer

Do we use dimensional analysis?

anonymous · Answer

No I don't think so

turingtest · Answer

I don't see why the rotation of the earth is given in ft/sec,
it should be given in a period or angular units like radians.

generally the formula for the velocity of a point on a rotating object of radius r from the center is$$v=r\frac{2\pi}{T}$$where T is the period (the time needed for one revolution) and r is the radius.

But your problem gives the velocity of the earth at the surface of the equator it seems, so I suppose you just need to convert the units of ft/sec into mi/hr.

what do you think James?