Final answer:
To find the circumference of the Earth at the equator, use the formula C = 2πr where r is the radius. Calculate the radius using the speed at the equator, then plug it into the formula to find the circumference.
Step-by-step explanation:
To find the circumference of the Earth at the equator, we can use the formula for calculating the circumference of a circle: C = 2πr, where C is the circumference and r is the radius.
The speed at the equator is given as 1660 km/h. We can convert this into the distance travelled in 1 hour by multiplying it by 1 hour (60 minutes) and converting to km: 1660 km/h * 1 hour = 1660 km.
Now we can solve for the radius using the formula: C = 2πr. Rearranging the formula, we have r = C / (2π).
Plugging in the value for C, we get r = 1660 km / (2π).
Finally, we can find the circumference by using the formula C = 2πr: C = 2π * (1660 km / (2π)). Simplifying, we get C ≈ 1660 km.