Water Streams Can Keep Light Inside

A horizontal stream of water leaves an opening in the side of a tank. If the opening is h metre above the ground and the stream hits the round D metre away, then what is the speed of water as it leaves the tank in terms of g, h and D ?

Take a bottle of cold water out of a refrigerator and keep it outside for a while. Observe the outer surface of the bottle. Drops of water can be observed on the outer surface of bottle.

Keep some freshly cut flowers in a solution of food colour. Wait for sometime for the days to rise in the flower, when the stem, of the flower is held up in light, coloured strands can be seen inside. Can this experiment demonstrate which tissue is conducting water up the stem ?

Assertion: We can protect electrically sensitive instruments by keeping them inside a metallic box. Reason: Conductors can maintain a uniform electric field inside them.

The continuous upward flow of water stream in tall trees is maintained due to ___________

A girl brings a positively charged rod near a thin neutral stream of water from a tap. She observes that the water stream bends towards her. Instead, if she were to bring a negatively charged rod near to the steam, it will–

How can we shield some instrument from magnetic field? Can we do it by keeping them inside a wooden box or iron box?