Question

give reason a. shocker are provided in vehicle

Answer 1

because the spring shockers observe the shop exerted on vehicle and does not lead the shock towards the passengers

Answer 2

(I presume you mean shocks. Correct me if I’m wrong.) Primarily to absorb and dampen road shock and return the vehicle to a smooth ride and maintain that ride. Shocks perform over a thousand oscillations per mile (and why they wear out, even if you just drive on the smoothest roads), from the little bumps and humps of as newly paved road that you don't see (or feel due to the shocks) to massive potholes to that final little lurch at the end of a stop. They are not designed to hold the weight of the vehicle, though heavy duty ones do aid in this. With the advent of independent and front wheel drive came the need for a dampening system capable of doing more work, hence the strut system. A lot of vehicles are now equipped with struts on front and shocks in the rear or struts at all four corners (though pickups and larger SUVs may still have both front and rear shocks). Hope that's what you were looking for.