When sun rays pass through a small hole in the foliage at the top of a high tree, they produce an elliptical spot of light on the ground. Explain why. When will the spot be a circle?

Sunrays pass through a pinhole in the roof of a hut and produce an elliptical spot on the floor. The minor and major axes of the spot are 6 cm and 12 cm respectively. The angle subtended by the diameter of the sun at our eye is 0.5° . Calculate the height of the roof.

When a ray of light passes through glass slab, refraction of light occurs___

When a source of sound passes us, whether it be a car horn or a train whistle, the pitch we hear goes from high to low. Explain why. Use any relation to support your explanation.

Noor, a young student, was trying to demonstrate some properties of light in her Science project work. She kept ‘X’ inside the box (as shown in the figure) and with the help of a laser pointer made light rays pass through the holes on one side of the box. She had a small butter-paper screen to see the spots of light being cast as they emerged. What could be the ‘X’ that she placed inside the box to make the rays behave as shown?