Write a program that calculates the annual cost of running an appliance. The program will ask the user for the cost per kilowatt-hour and the number of killowatt-hours the appliance uses in a year:
Click here to go back to the main menu.Enter cost per kilowatt-hour in cents 8.42 Enter kilowatt-hours used per year 653 Annual cost: 54.9826
When a brick is dropped from a tower, it falls faster and faster until it hits the earth. The speed v is given by
Here v is the speed in feet per second, t is the time in seconds, and g is 32.174. Write a program that asks the user for the number of seconds and then prints out the speed.v = 1/2 g t2
One hundered miles per hour is 146.67 feet per second. Use your program to determine approxiamtely how long it takes the brick to reach that speed. Click here to go back to the main menu.Enter the number of seconds 5.4 Speed of the brick: 469.092 feet per second
The base 2 logarithm of a number is defined by:
For examplelog2 X = n if 2n = X
Write a program that inputs a number and outputs its base 2 logarithm. Use floating point input. This problem would be easy, but the Math package does not have a base 2 logarithm method. Instead you have to do this:
Here, loge X is the natural logarithm of X. This function you do have in the Java Math package:log2 X = (loge X) / (loge 2)
When you use this, X must be a double. Write the program so that the user can enter floating point numbers.Math.log( X )
Click here to go back to the main menu.Enter a double: 998.65 Base 2 log of 998.65 is 9.963835330516641
The harmonic mean of two numbers is given by:
This is sometimes more useful than the more usual average of two numbers. Write a program that inputs two numbers (as floating point) and writes out both the usual average (the arithmetic mean) and the harmonic mean.H = 2 / ( 1/X + 1/Y )
Click here to go back to the main menu.Enter X: 12 Enter Y: 16 Arithmetic mean: 14.0 Harmonic mean: 13.714285714285715