2019 Year 12 IB Extended Essays

THE PHYSICS OF THE ROLLER COASTER

are circular or curved, the momentum of the roller coaster helps it to move along the path

and complete the loop. However, because the loop is curved, the velocity of the roller coaster

always changes but overall, the momentummakes the roller coaster moves in a path the track

dictates it and, in this case, the roller coaster moves in a circular motion.

G-force refers to the amount of force that the Earth gravitational field acts on an object when

it lies in the Earth’s gravitational field (How it works team, 2015). 1 g on Earth is equal to 9.81 / −2 . However, these g-forces in roller coaster only refer to acceleration forces. These acceleration forces are interacted by the roller coaster in a way that it is able to recreate the

feeling of weightlessness. The acceleration force of inertia will act the opposite of the force

that the roller coaster exerts on our body since inertia resists change of motion. When the

roller coaster plummets, riders fell weightlessness because the inertia is resisting the

downward force of gravity. When the net force is 0 we feel weightless but when the roller

coaster is climbing a hill, we feel heaviness because both gravity and inertia of our bodies are

pulling us downwards (Harris & Threewitt, n.d.).

2.3 Clothoid loops and banked turn As I have mentioned above, roller coaster loops are not exactly circle. They are tear shaped

and called clothoid loop. This loop is designed to reduce the central acceleration and the g-

force effect on the riders. Since circular loop has a larger uniform radius, greater entry speed

is required and hence higher hill is needed.

With higher entry speed, the central acceleration will increase greatly and therefore the g-

force. This means the inertia of the riders will be larger because it has to counteract a larger

force exerted on the rider (Clothoid Loop). G-force could potentially cause the riders to black

out as it pulls the blood away from their brains. This concept of g-force effect is even utilized

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IB Diploma