Consider Arius the brightest star visible from Earth which is located 4.2 light-years away. Let's assume that Pxima S is one of Saturn's moons. Dr. Alex and his team, are interested in constructing an observatory building on Pxima S in order to determine if Saturn is orbiting the sun. Determine what practical obstacles might prevent this experiment from succeeding if the size of the moon is not an issue.

A person in a park uses a 4.0 cm tall flat mirror, which he holds 30 cm away from his eyes. Through the mirror, he observes a tree in the distance. The tree fills the mirror view from its base to its top. If the tree is 15 m from the mirror, what is the tree's height?

A fashion designer tries on a new suit while standing in front of a tall mirror that is located 210 cm away. The distance from the designer's eyes to his feet is 115 cm. What would be the image distance from the designer's eyes to his feet as seen in the mirror?

Two flat mirrors (M ₁ and M ₂) are perpendicular to each other. A monochromatic, laser beam hits the surface of M ₁, at an angle θ, 15.0 cm from the intersection of the two surfaces. After reflection from M ₁, the beam of light hits the surface of M ₂ 25.0 cm away from the intersection. Determine the angle of incidence θ .