Last spring, I set out to ride my bicycle to the beach. Unfortunately, my front tire picked up a tack and I had to stop riding after another 15 minutes. Given that I rode at a constant speed of 6 mph and the radius of my bicycle tires is 2 feet, how high above the ground was the tack when I stopped.

1 answer

To determine the height above the ground of the tack, we can visualize the situation as a circular path with a radius of 2 feet. When the tack was picked up by the front tire, it must have traveled a distance equivalent to 15 minutes of riding at 6 mph.

First, let's calculate the distance traveled in 15 minutes. Since we know that speed equals distance divided by time, we can rearrange the formula to solve for distance: distance = speed × time.

The speed is given as 6 mph, which we can convert to feet per minute: 6 mph * (5280 feet/1 mile) * (1 hour/60 minutes) = 528 feet/minute.

The time is given as 15 minutes.

Therefore, the distance traveled is: distance = 528 feet/minute * 15 minutes = 7920 feet.

Since the distance around a circle is equal to the circumference, we know that the distance traveled is equal to 7920 feet = 2πr, where r is the radius of the circle.

Rearranging the formula to solve for r, we get: r = distance / (2π) = 7920 feet / (2π) ≈ 1258.99 feet.

Since the radius of the bicycle tire is given as 2 feet, we can calculate the height of the tack above the ground as the difference between the radius of the circle formed by the tack's position and the radius of the bicycle tire: 1258.99 feet - 2 feet = 1256.99 feet.

Therefore, the tack was approximately 1256.99 feet above the ground when you had to stop riding.