# Expert works out the key to the perfect pancake toss

On pancake day, with so many of the sweet and savoury dishes being served up, it's important to know what makes the perfect toss.

Dr Mark Hadley of the Department of Physics at the University of Warwick has been working out all the relevant equations in order to get the best flip of a pancake.

He split the sums into four sections:

• UP and Down

Dr Hadley worked out that a respectable pancake toss should be 0.5 metres high, and in order for that to happen, the launch of the pancake out of the pan needs a velocity of 3 metres per second. That means the pancake will be in the air for 0.6 seconds.

But be careful - just 2 metres per second more and your pancake will be hitting the ceiling!

• The Spin

The pancake needs to flip through half a turn, or 180 degrees, and it has to do that while in the air.

Dr Hadley's equation worked out that it needs to have angular momentum of about five radians per second - basically, make sure you get a good whip on the pan so the pancake makes a complete half-turn!

• Optimum Height

This one depends on the length of your arm, so you know how much you need to swing the pan.

There are three types of toss, according to Dr Hadley.

The first is 'the housewife's toss'. This is where the upper arm hardly moves, and the forearm swings upwards from the elbow. With the length of the forearm typically 60cm, that means the pancake needs to get to 0.5 metres in order to get a 180 degree flip.

The second is 'the show off'. This is a two-armed throw for someone who wants to stand out from the crowd... or someone flipping with a cast-iron pan. With arms outstretched, swinging from the shoulder, the height required for the exact flip is 0.7 metres - but watch out for low ceilings.

The third is 'the chef'. This is the quick, efficient flick of the wrist. Holding the pan by the handle, but near the rim, means you only need to get the pancake 16cm high - just enough to clear the pan and get a full toss.

• Aerodynamics

Because pancakes are flat, they tend to float back down to the pan, so that can help.

But it certainly hinders the take off. Because of its span, there is air pressure between the pancake and the pan, so it is important to make sure the batter isn't stuck to bottom, and that it can move freely from side to side.

After that, air pressure can be lowered by reducing the size of the pancake, because that helps air get underneath.

And finally, cook the pancake until it bubbles and blisters so the bottom is rough. That will help it slide off the pan when tossing.