There are three paths `a,b and c` of a projectile projected from point `P` as shown in (Fig. 5.62). Prove that `v_1 gt v_2 and v_3 = v_4`. Which path is correct ?
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Explanation

Let `prop` be the angle of projection with incline and `beta` be the angle at which projectile strikes the plane.
Then `tan prop = v_3//v_1 and tan beta = v_4//v_2`.
Here the magnitude of velocity component initially and finally along y - axis willm be same, because `S_y = 0`.
Hence, `v_3 = v_4`. But verlocity component along x - axis goes on decreasing. So `v_2 lt v_1`. Hence, from above equations, `tan beta gt tan prop rArr beta gt prop`. Hence, appropriate path should be `b`.
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