Light, reflection & shadows
Take your time. Show your thinking.
1. What optical instrument uses two mirrors angled at 45° inside a tube to let an observer see over obstacles: a periscope or a stethoscope?
Light Ray (Straight Line) · Angle i = Angle r 2. How does light travel through a uniform medium such as air or vacuum: in straight lines, or in curved loops?
Light Ray (Straight Line) · Angle i = Angle r 3. What type of lens is thicker in the middle than at the edges and brings parallel light rays together to a focal point: a convex (converging) lens or a concave lens?
Light Ray (Straight Line) · Angle i = Angle r 4. According to the law of reflection on a flat plane mirror, how does the angle of reflection compare to the angle of incidence: they are equal, or the angle of reflection is twice as large?
Light Ray (Straight Line) · Angle i = Angle r 5. What do we call the bending of a light ray when it passes at an angle from air into water or glass (due to a change in speed): refraction or absorption?
Light Ray (Straight Line) · Angle i = Angle r 6. Why does a straight pencil standing partly in a glass of water look bent at the water surface: refraction of light rays leaving the water, or the water bends the wood?
Light Ray (Straight Line) · Angle i = Angle r 7. Why does an opaque object cast a dark shadow when placed in front of a torch: light travels in straight lines and cannot pass through the opaque object, or the object absorbs darkness?
Light Ray (Straight Line) · Angle i = Angle r 8. Why does a smooth mirror form a clear image while white paper does not: specular reflection vs diffuse scattering, or paper absorbs all light?
Light Ray (Straight Line) · Angle i = Angle r 9. Which of these is a luminous object (emits its own light): the Sun or the Moon?
Light Ray (Straight Line) · Angle i = Angle r 10. Does light require a material medium (like air) to travel, or can it travel through the vacuum of space?
Light Ray (Straight Line) · Angle i = Angle r 11. Why do people often wear light-coloured or white clothing in hot sunny weather: white surfaces reflect most sunlight and stay cooler, or white absorbs all heat?
Light Ray (Straight Line) · Angle i = Angle r 12. What astronomical event occurs when Earth passes directly between the Sun and the Moon, casting Earth’s shadow onto the Moon: a lunar eclipse or a solar eclipse?
Light Ray (Straight Line) · Angle i = Angle r