Centripetal force calculation. Animation of a racing car on a race track, turning around sloping banks at each end. The diagrams and labels show the calculation of the centripetal force acting on the car and driver as the car turns through the banked sections. The car turns through a circle of radius 'r' and centre 'C'. Towards the end of the clip, the diagram shows the car on the bank at an angle of theta. The weight (mg) acts downwards, equal to mass (m) multiplied by gravity (g). The reaction force acting perpendicular to the race track can be resolved by trigonometry into two components. The vertical component is the reaction force multiplied by the cosine of the angle theta. This vertical component is equal to the weight. The horizontal component is the reaction force multiplied by the sine of the angle theta. This horizontal component is equal to the mass of the car (m) multiplied by the square of its velocity (v), divided by the radius of the turning circle (r).