A Small Object Slides Along the Frictionless Loop-The-Loop with a Diameter

Multiple Choice

A small object slides along the frictionless loop-the-loop with a diameter of 3 m.What minimum speed must it have at the top of the loop in order to remain in contact with the loop?

A) 1.9 m/s
B) 3.8 m/s
C) 5.4 m/s
D) 15 m/s
E) 29 m/s