The aim of this experiment is to:
□ Explore the equations of uniform accelerated motion and investigate the relationship between displacement and time □ Determine the magnitude of deceleration due to friction. □ Assess the effect of mass on the car’s accelerated motion.
Hypothesis – A car moving in a straight line with a non-zero initial velocity will finally come to a rest as a result of friction, given that the car has no engine or external tractions. This motion can be considered as a uniform accelerated motion because: 1. The car is moving in a horizontal straight line so weight is cancelled by the normal reaction force from the ground. The only other force existed is the friction between the car and the surface therefore it will be equal to the net force 2. According to the formula Fr = μN, the amount of the friction depends on two factors: the friction coefficient and the normal reaction force, both of which are fixed. Therefore the amount of friction is constant throughout the motion 3. According to Newton’s Second Law F = ma, a constant net force will result in a uniform acceleration (deceleration). The acceleration is negative in this case as cars are slowing down to a rest.
For convenience, this decelerated motion can be inverted into an equivalent motion in which the car is acceleration from rest. It should follow the equation of x = ut + 1/2 at2,
where x = distance traveled, u = 0 (seen as the initial velocity but actually is the final velocity which is zero at rest), a = acceleration (actually deceleration) and t = time taken during that motion. This formula can be simplified as x = 1/2 at2. We will measure the variables of x and t to verify this relationship and determine the magnitude of this deceleration, which can be derived from the gradient of the regression line of x against t2.
Theoretically the mass of the car should not influence its deceleration because: Friction is the net force, Fr =μN = μmg (as...