Two particles A and B start simultaneously from the same point and move in a horizontal plane. A has an initial velocity `u_(1)` due east and acceleration `a_(1)` due north. B has an initial velocity `u_(2)` due north and acceleration `a_(2)` due east. Then :

Options

A. They must collide at some point
B. They will collide only if `a_(1)u_(1) = a_(2)u_(2)`
C. their paths must interesect at same point
D. If `u_(1)gtu_(2) " & " a_(1) lta_(2)`, the particles will have the same speed at some point

Answer

B, C, D

Explanation

`u_(1)t=(1)/(2)a_(2)t^(2),u_(2)t=(1)/(2)a_(1)t^(2)`
`(u_(1))/(u_(2))=(a_(2))/(a_(1))`
`u=sqrt(u_(1)^(2)+a_(1)^(2)t^(2))v =sqrt(u_(2)^(2)+a_(2)^(2)t^(2))`