# Challenge 2013-06

### Curriculum Challenge 1.5

1. Write a program that asks the user for 2 numbers and what calculation to perform (+, -, / or *), then uses a different subroutine to do the required calculation.
2. Get the user to enter a word and use the Dictionary method to get its definition.
Create a subroutine to check if it can be used as a noun, and if it is, use a second subroutine to get and print the first noun definition.

### Small Challenge 1

Write a program that outputs a multiplication table, using an input multiplier and maximum to multiply it by.
For example multiplier 7 and maximum 12.

• 1 x 7 = 7
• 2 x 7 = 14
• 11 x 7 = 77
• 12 * 7 = 84

### Small Challenge 2

It is useful to be able quickly do approximate maths in your head.
To help, write a program that shows approximate (to the nearest integer) divisors of 100.
For example:

• 100/7 ~ 14
• 100/17 ~ 6

### Maths Challenge

Write a program to calculate the area of regular polygons (equal side lengths and equal internal angles).
The first is an equilateral triangle, the second a square, etc.
The user enters the number of sides and their length.
For large number of sides, the area should approximate that of a circle.

### Game Challenge

Write a repro of the Tron game, Google for it, here is a simple scratch version.

### Physics Challenge

Calculate the time for a satellite to orbit the Earth at different altitudes.
What altitude is a geostationary orbit (orbits in 24 hours).
G*M*m/r/r = m*v*v/r

• G is gravitational constant  6.67384 E-11 m3 kg-1 s-2
• M is the Earth mass 5.972 E24 kg
• m is the satellite mass (orbit doesn’t depend on this)
• v is the satellite velocity (m/s)
• r is the satellite distance from the Earth center

The Earth radius is 6371 km

### Community Challenge 1

(By Nonki)

1. Write ASCII code table.
2. Make any kind of roulette (wheel).

### Community Challenge 2

(By Jibba Jabba)
When people register on a theatre website, the email address is used as the login name and the user is requested to enter a password to use with the account.