The radius of a geographical globe is 60cm. Find the length of the parallel of latitude 60oN
A
\(66\pi cm\)
B
\(60\pi cm\)
C
\(30\pi cm\)
D
\(15\pi cm\)
E
\(6\pi cm\)
Verified Correct Answer: B.
Step-by-Step Mathematical Solution
The radius of the globe (sphere), R = 60 cm.
At latitude 60^\circN, the radius of the parallel of latitude is given by:
r = R \(\times \cos(60^\circ)\)
\(\cos(60^\circ) = \frac{1}{2}\)
r = 60 \(\times \frac{1}{2} = 30 \text{ cm}\)
The length of the parallel is the circumference of this circle:
\(\text{Length} = 2\pi r = 2\pi \times 30 = 60\pi \text{ cm}\)
This is the actual distance around the globe along the 60^\circN parallel.
Source: Myschool Past Questions Archive (Record #26339)