Question Detail
Question
A hot wheels track has a vertical loop with a radius 20 cm. What is the minimum speed the car can have at the highest point without falling off the track?
Correct Answer
Option C is the correct answer.
Detailed Explanation
At the highest point, the minimum speed to just maintain contact is when the centripetal force is provided entirely by gravity: mg = mv²/r => v = √(gr). r = 0.2 m, g = 9.8 m/s², v = √(9.8 × 0.2) = √1.96 = 1.4 m/s.
Hint
At the top of the loop, the minimum speed is √(gr).