Question

On a stopwatch, the tip of the second hand moves 2 cm in 15 seconds. How long is the second hand (to the nearest tenth)?

12.6 cm
1.3 cm
6.3 cm
30.0 cm

Answer 1

@agent0smith

Answer 2

15 seconds is a quarter of a minute, right?

A quarter of a circle is how many radians?

Answer 3

16

Answer 4

...?

Answer 5

whats a radian again

Answer 6

A unit for measuring angles. There is 2pi radians in a circle.

Answer 7

There is 2pi radians in a circle. A quarter of a circle is how many radians?

Answer 8

now use \[\Large s = r \theta\]again like last night

You need to find r.

You have the angle. You have the arc, s, which was the 2cm