It's best to do it in a darkened bathroom or kitchen at the sink or washbasin. You'll need an old clear, plastic drinks bottle, a flashlight (torch), some aluminum foil, and some sticky tape.
1. Take the plastic bottle and wrap aluminum foil around the sides, leaving the top and bottom of the bottle uncovered. If you need to, hold the foil in place with sticky tape.
2. Fill the bottle with water.
3. Switch on the flashlight and press it against the base of the bottle so the light shines up inside the water. It works best if you press the flashlight tightly against the bottle. You need as much light to enter the bottle as possible, so use the brightest flashlight you can find.
4. Standing by the sink, tilt the bottle so the water starts to pour out. Keep the flashlight pressed tight against the bottle. If the room is darkened, you should see the spout of water lighting up ever so slightly. Notice how the water carries the light, with the light beam bending as it goes!
1. Take the plastic bottle and wrap aluminum foil around the sides, leaving the top and bottom of the bottle uncovered. If you need to, hold the foil in place with sticky tape.
2. Fill the bottle with water.
3. Switch on the flashlight and press it against the base of the bottle so the light shines up inside the water. It works best if you press the flashlight tightly against the bottle. You need as much light to enter the bottle as possible, so use the brightest flashlight you can find.
4. Standing by the sink, tilt the bottle so the water starts to pour out. Keep the flashlight pressed tight against the bottle. If the room is darkened, you should see the spout of water lighting up ever so slightly. Notice how the water carries the light, with the light beam bending as it goes!