In dealing with motion of projectile in air, we ignore effect of air resistance on motion.This gives trajectory as a parabola as you have studied. What would the trajectory look like if air resistance is included? Sketch such a trajectory and explain why you have drawn it that way.

In projectile motion , if air resistance is ignored, the horizontal motion takes place with:

What is a projectile? What do you understand by trajectory? Show that motion of a projectile fired horizontally is a prabola.

Deep sea divers have been using the compressed air containing N_2 in addition to O_2 for breathing. When the sea divers breathes in compressed air at a depth, more N_2 dissolves in the blood and other body fluids than would dissolved at the surface because the pressure at the depth is far greater than surface atmospherice p ressure. when the diver comes towards the surface, the pressure decreases and N_2 comes out of the body quickly forming bubbles in the stream which restrict blood flow and affect the transmission of nerve impuses. this results into a condition called 'the bends' which is dangerous and painful. To avoid this condition, professionals now use air diluted with helium. As a student of chemistry, can you analyse as to why helium is used?

A cricket bowler releases the ball in two different ways (a) giving it only horizontal velocity and (b) giving it horizontal velocity and a small downward velocity. The speed v_s at the time of release is the same . Both are released at a height H from the ground . which one will have greater speed when the ball hits the ground ? Neglect air resistance.

A cricket bowler releases tha ball in two different ways giving it horizontal velocity and a small downward velocity and the speed v_s at the time of release is the same. Both are relased at a height H from the ground. Which one will have greater speed when the ball hits the ground? Neglect air resistance.