A student stands on a calibrated bathroom scale while riding through a full vertical…
PHYSICS · Multi-part · CBSE · Physics · Laws of Motion · Laws of Motion
Problem
A student stands on a calibrated bathroom scale while riding through a full vertical loop on a roller-coaster train. The loop is perfectly circular and has a radius of 12m. The student’s true weight is 620N. The train enters the loop with sufficiently large speed so that the wheels remain in contact with the track at all times.
For each of the four locations listed below, the scale is oriented so it always reads the normal force exerted on the student by the seat.
(a) Rank the four locations from greatest to least scale reading. If any have equal readings, state that explicitly.
(b) Provide a clear explanation for the ranking you gave in part (a), identifying the forces acting on the student and discussing how the direction of the student’s acceleration at each point affects the scale reading.
(c) At which of the four locations could the scale possibly read zero? Explain the physical conditions necessary for that to occur, and relate them to the motion of the roller coaster.
(d) Describe how the student’s apparent weight would change if the radius of the loop were doubled while the speed profile remained the same. Justify your answer qualitatively, making reference to relevant physical relationships.