calculateAverageSpeed()

Step 1: Declare the function and parameters.

We first need to declare a function named calculateAverageSpeed. This function should accept two parameters: distance which is the total distance covered, and time which is the total time taken to cover that distance. Both parameters are numeric and represent distance in kilometers and time in hours respectively.

function calculateAverageSpeed(distance, time){
}

Step 2: Calculate the average speed.

Next, we will calculate the average speed. The average speed can be calculated by dividing the distance by the time. We will store the result in a variable called averageSpeed.

function calculateAverageSpeed(distance, time){
  let averageSpeed = distance / time;
}

Step 3: Handle edge cases.

There could be cases where the time or distance is zero. In Physics, speed is undefined when time is zero, therefore we will handle this case by returning 0 when time is zero.

function calculateAverageSpeed(distance, time){
  if(time === 0) {
    return 0;
  }
  let averageSpeed = distance / time;
}

Step 4: Return the Result.

After calculating the average speed, the function should return the result.

function calculateAverageSpeed(distance, time){
  if(time === 0) {
    return 0;
  }
  let averageSpeed = distance / time;
  return averageSpeed;
}

Step 5: Demonstration

Now we can call the function with some sample input to see if it works as expected.

console.log(calculateAverageSpeed(100, 2)); // Expected output: 50

Conclusion

With this, we have built a function to calculate average speed in JavaScript. This function performs input validation and handles division by zero effectively. This function can be used to calculate average speed in any application that requires it. Following is the complete function code for reference:

function calculateAverageSpeed(distance, time){
  if(time === 0) {
    return 0;
  }
  let averageSpeed = distance / time;
  return averageSpeed;
}