To calculate the force acting on a conductor, use the formula F = ILBsin(θ), where I is the current, L is the length of the conductor, B is the flux density, and θ is the angle between the conductor and the magnetic field. In this case, the conductor length is 200mm, the flux density is 2 tesla, and the current is 5A. If the angle is not specified, it can be assumed to be 90 degrees for maximum force. The forum emphasizes that users should work through the calculations themselves using the provided formula and values. Understanding the formula and ensuring correct unit conversion is essential for accurate results.