In experiment 1, unpolarized light falls on the polarizer in the figure. The angle of the polarizer is = 58.0°. In experiment 2, the unpolarized light is replaced by light of the same intensity, but the light is polarized along the direction of the polarizer's transmission axis. (a) By how many additional degrees must the analyzer be rotated, so the light falling on the photocell has the same intensity as it did in experiment 1? (b) Is (1) increased or (2) decreased by this addition rotation? Give the number of the correct choice.

To find the answers to these questions, we need to understand the basics of polarized light and the behavior of polarizers and analyzers.

(a) In Experiment 1, unpolarized light falls on the polarizer. This means that the light waves vibrate in all possible directions perpendicular to their direction of propagation. The polarizer only allows the component of light waves vibrating in a specific direction to pass through, while blocking the component vibrating in the perpendicular direction.

In Experiment 2, the light is already polarized along the direction of the polarizer's transmission axis. This means that the polarizer allows all of this polarized light to pass through.

To ensure that the light falling on the photocell has the same intensity as in Experiment 1, the analyzer must be rotated to block the component of light that is aligned with the polarizer's transmission axis. Since the light in Experiment 2 is already polarized along the transmission axis, we need to rotate the analyzer by 90 degrees to block this component.

Therefore, the additional rotation required for the analyzer is:
90° - 58.0° = 32.0°

So, the analyzer should be rotated by an additional 32.0 degrees.

(b) The angle (1) (the angle between the transmission axes of the polarizer and the analyzer) is decreased by this additional rotation. In Experiment 1, = 58.0°, but after rotating the analyzer by 32.0°, the new angle (1) would be:
58.0° - 32.0° = 26.0°

Therefore, (1) is decreased by this additional rotation.

The correct choice is (2) decreased.