A solid is put in a bucket of water. It floats just below the surface of the water. What do you think is the density of the object with relation to the density of water? Open Answer »
Differentiate among opaque, translucent and transparent materials, giving one example of each. Open Answer »
Chalk, iron nail, wood, aluminium, candle, cotton usually look different from each other. Give some properties by which we can prove that these materials are different. Open Answer »
Why do you think oxygen dissolved in water is important for the survival of aquatic animals and plants? Open Answer »