Light Refraction with Gel Balls. #Exp5

WHAT IS INCLUDED IN THE KIT

• 1 Bag with Transparent Gel Balls:
  • You can choose between:
    • 100g of dry beads can be made up to 100L. Ball size: 2.5-3mm dry - 1-1.5cm hydrated with water.
    • or 1kg up to 1000l of water. Ball size: 2.5-3mm dry - 1-1.5cm hydrated with water.
• Not included: decorative elements and floating candles, which you will have to buy in a shop.

DETAILED STEP-BY-STEP

• Take the gel balls.
• Every 10 grams of balls will absorb up to 1 litre of water. It will take 4-5 hours for them to be fully hydrated.
• Add the balls in the vase, place the decorative elements.
• Pour in water and you will see how the objects appear to be floating.

TECHNICAL EXPLANATION

Refraction is the change in the direction of propagation of a wave as it passes through an interface between two media with different refractive indices. This occurs because the velocity of the wave is different in each medium.

When an object is immersed in water, the light entering the object passes through the air-gel interface and is refracted due to the difference in the refractive indices of the air and the object. Then, when light passes through the gel-water interface, it is refracted again due to the difference in refractive indices.

However, since the gel ball has the same refractive index as water, there is no difference in the speed of light in the gel and in the water, so there is no refraction when light passes through the gel-water interface. In this case, light enters the gel ball and will leave it without changing its direction of propagation, so the gel ball would appear "invisible" from the outside. In this way, only the decorative elements you have placed are visible.

SEE OTHER ACTIVITIES

You can see other activities and kits here: Activity kits