The size of your nose would be the right size for a large nosecone
Well if you are using the standard 1 litre bottles, it should be the diameter of the bottle, and about 10cm tall.
the nosecone
no, it is impossible to take a life size rocket and shrink it to fit your shoe and call it, a Rocket shoe.
The Saturn 5 rocket stood 365 ft tall.
7, 8, maybe 9
On average, they are about the size of a city block.
The nosecone section of a rocket is used to cut down the wind resistance whilst passing through the atmosphere.
the nosecone
rounded
To reduce drag while passing through the atmosphere.
heat barrier
There does not appear to be a "best" size. It depends on a number of factors, to include the bottle used (brand of drink & manufacturer), type of rocket, distance aiming for. One common element to consider is drag. Larger fins have greater surface and mass which will directly affect the altitude your rocket can reach.
Saturn 5 was the best rocket.
It's a question of air resistance - too much and you burn up, too little and you don't slow down enough.
The size of fins affects the stability and angle, small fins are best.
Saturn V WAS the best rocket launcher.
Recovery wadding is a flame-resistant tissue paper placed in the tube of a model rocket before the recovery device and nosecone. Its purpose is to prevent the parachute or streamer from being burned / melted when the ejection charge goes off.
Saturn 5 was the best rocket.