The earth rotates once per day about an axis passing through the north and south poles. true or false

False.

Explanation: The Earth rotates once per day in direction from East to West. The rotation of the Earth daily is responsible for day and night experienced, the areas of the Earth facing the Sun experiences day time while the areas of the Earth away from the Sun in the Earth's shadow experiences night time.

While the revolution of the Earth around the gives rise to a year, as it takes 365 days for the Earth to go round the sun.

the duration of a photographic flash is related to an rc time constant, which is 0.100 μs for a certain camera.