That depends upon how much mass has been moved over that 30 minute walk.
Calculating the number of kilojoules burnt depends on a number of variables. These variables speed at which one is walking and ones' body weight. In the related links I have included a link to wolfram alpha. By inputting your query for example "30 minute walk 50kg 10km/h" wolframalpha will give you the number of kilojoules based on these variables
It works like this:10 meters / 3.09 seconds * 30 seconds / half minute = 97.09 meters / half-minute
If you walk for 30 minutes, the distance you walk totally depends on your speed. The majority of people can walk approximately 2 whole miles in a 30 minute time span.
30 seconds in half a minute (there are 60 seconds in a minute)
At 30 mph, a car is traveling at 2,640 feet per minute.
30 Minute Meals - 2001 30-Minute Legacy was released on: USA: 30 April 2006
Find how many miles he walks in one minute by division.
Two 30 minute Halves. Four 15 Minute Quarters
30 acres of tropical rainforest is lost every minute!!!