Final answer:
To calculate the time spent above 40 meters on a Ferris wheel, we analyze the wheel's structure and use trigonometry to find the proportional time of the ride corresponding to the arc above the 40-meter mark.
Step-by-step explanation:
Calculating Time Spent Above 40 meters on a Ferris Wheel
To determine how many minutes of the ride on the Ferris wheel are spent higher than 40 meters above the ground, we need first to understand the wheel's structure and motion. Given that the Ferris wheel has a diameter of 50 meters and is boarded from a platform 4 meters above the ground, we can calculate the highest and lowest points riders will reach during the ride. The highest point of the wheel will be 50 meters (the radius) plus 4 meters (the platform height), totaling 54 meters. The lowest point will be 4 meters (platform height) above the ground since the diameter is equal to twice the radius and the wheel's lowest point touches the platform level.
Because riders want to be above 40 meters, we're interested in the segment of the ride where they are between 40 meters and the maximum of 54 meters above the ground. This range covers a portion of the wheel's circumference. If the wheel's highest point is at 12 o'clock and the loading platform is at 6 o'clock, then the 40-meter height will be somewhere between 6 o'clock and 12 o'clock.
Using the fact that the Ferris wheel completes one revolution in 4 minutes, we can find the time spent over 40 meters by calculating the angle θ that corresponds to the arc between 40 meters and 54 meters above the ground. The 40-meter height will fall at the point where the vertical distance from the top of the wheel equals the wheel's radius minus 40 meters. Using this, we can use trigonometry to find θ, and then convert this angle to a proportion of the full revolution time to determine the time spent on this segment of the ride.