Program to demonstrate the use of Binary Search to search a given element in a sorted array in ascending order.

Sure, here is a simple Python program that demonstrates the use of Binary Search to search a given element in a sorted array in ascending order.

def binary_search(arr, low, high, x):
 
    # Check base case
    if high >= low:
 
        mid = (high + low) // 2
 
        # If element is present at the middle itself
        if arr[mid] == x:
            return mid
 
        # If element is smaller than mid, then it can only
        # be present in left subarray
        elif arr[mid] > x:
            return binary_search(arr, low, mid - 1, x)
 
        # Else the element can only be present in right subarray
        else:
            return binary_search(arr, mid + 1, high, x)
 
    else:
        # Element is not present in array
        return -1
 
# Test array
arr = [2, 3, 4, 10, 40]
x = 10
 
# Function call
result = binary_search(arr, 0, len(arr)-1, x)
 
if result != -1:
    print("Element is present at index", str(result))
else:
    print("Element is not present in array")

This program first defines a function binary_search that takes a sorted array arr, the lowest index low, the highest index high, and the element x to be searched. It then checks if the element is present at the middle of the array. If it is, it returns the index. If the element is smaller than the middle element, it performs the search on the left subarray. If the element is larger, it performs the search on the right subarray. If the element is not found, it returns -1. The program then tests this function with a test array and a test element.