# trigonometry

posted by
**michelle** on
.

The minute hand of a clock is 8 inches long. How far does the tip of the minute hand move in 30 minutes? How far does it move in 20 minutes?

For 30 min. I got 8pie inches. For 20 mins., I got (16pie/3)inches. but i don't know if these answers are correct. if my answers are wrong, please show me the steps to solving this.

Thanks.

Arc distance= radius*angular speed*time

angular speed for a minute hand is 1 rev per hour, or 2PI rad/hr

for 20 min:8in*2PI/hr*1/3 hr

You are correct.