If two equal forces act perpendicularly upon each other, then the angle between the resultant force and a horizontal surface will be

Explanation

When two equal forces are applied perpendicularly to each other, they create a right angle. In such a case, the resultant force can be determined using the Pythagorean theorem. The magnitude of the resultant force is equal to the square root of the sum of the squares of the magnitudes of the two forces. Since the two forces are equal, their magnitudes are the same. Therefore, if we consider each force to have a magnitude of "F," the magnitude of the resultant force will be: Resultant force = √(F^2 + F^2) = √(2F^2) = √2F Now, when the resultant force is resolved into horizontal and vertical components, each component will have a magnitude of √2F. Since the vertical component is equal to the force acting vertically, the angle between the resultant force and the horizontal surface will be 45 degrees. Therefore, the correct option is C, 45 degrees.