Tom Cruise has one of these. It’s a Bugatti Veyron Super Sport, one of the fastest production cars in the world this year. It could go even quicker but the speed has been limited because the tyres won’t be able to handle it if it goes faster.
A newer contender is the Hennessy Venom which outstrips the Bugatti and actually costs less. The Koenigsegg Agera RS is faster still, at 277mph, but, wait – the big news next year will be that Elon Musk’s Roadster will outstrip them all – an electric car able to do 0-60 in a blistering 1.9s and an as yet unannounced top speed.
Q: Why do cars have a top speed?
A: When the forward thrust of the engine is balanced by the resistive force of air pushing back against it, all forces are in equilibrium and so there’s no change in speed.
Have you noticed, a 300bhp sports car can go faster than a 300bhp tractor, since the air slides over the sports car more efficiently so it can go faster before the air resistance is as large as that experienced by the tractor.
When a parachutist opens his chute, his weight is quickly balanced by the push of air under the canopy, so he falls at a steady speed. We recall that weight is a force. Unbalanced forces change a body’s state of motion (speed it up or slow it down. Here’s the textbook stuff.
An object falling vertically has two forces acting on it-weight acting downwards and air resistance acting upwards. At the beginning of its fall, travelling slowly, weight is larger than air resistance, so it accelerates downwards.
As speed increases, weight stays the same but air resistance increases, so the net force and consequent acceleration decreases.
When air resistance and weight are the same, net force is zero and the body falls at a steady speed. (AS students – Newton 1) This is called TERMINAL VELOCITY.
Now download terminal-velocity-2and try a terminal velocity experiment yourself. My son showed me this when he went to University. I was surprised – perhaps you will be too.