Take a moment to understand this apparatus: Current passes through a rigid copper conductor mounted to a wood plate. The wood plate is mounted on a scale which measures the downward force exerted on the conductor. The scale is adjusted to read zero when no current flows. A magnet is placed next to the conductor, on a stand that is separate from the scale. When current flows through the conductor, the the interaction with the magnetic field causes a downward force on the conductor, which we can read on the scale. Which force is measured by the scale