Velocity of sound waves in air is 330m/sec . For a particle sound wave in air, a path difference of 40 cm is equivalent to phase difference of 1.6π . The frequency of this wave is? A. 165 Hz B. 150 Hz C. 660 Hz D. 330 Hz

What type of questions asked from the lesson of magnetic effect of electric current 

Wavelength of green light is

A) 400-450 nm

B) 500-550 nm

C) 660-720 nm

D) 720-800 nm

What is the difference between anaerobic & aerobic respiration? Name some organism that uses the aerobic mode of respiration?

What are the main components of our environment? Explain each of them briefly.

What are examples of hydrotropism plants?