This week’s questions

How do drivers of a train pulled by two engines control (the speed and brakes) of the second engine when they are sitting in the front engine (first one)?

Raj Kumar Gupta, Balangir, Odisha

Why do we have two nostrils?

Ananthu Krishna S. Kochi, Kerala

If we pinch ourselves we feel hurt, but when we tickle ourselves we don’t laugh. Why?

Ashwin Kumar R., Bangalore

Why do we have dreams while sleeping? Do we get mentally rested while dreaming?

Miniketan Khumukcham, Kakching Khunou, Manipur

How the height above sea level of a place measured when the sea is far off ?

P. Surendranath, Kochi, Kerala

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