Two particles A and B are placed in gravity free space at `(0, 0, 0) m and (30, 0, 0) m` respectively. Particle A is projected with a velocity `(5hat i + 10 hat j + 5 hat k) ms^-1,` while particle B is projected with a velocity `(10 hat i + 5 hat j + 5 hat k) ms^-1` simultaneously. Then,A. they will collide at `(10, 20, 10) m`B. they will collide at `(10, 10, 10) m`C. they will never collideD. they will collide at 2 s

Two particles A and B are placed in gravity free space at `(0, 0, 0) m

1.	Two particles A and B are placed in gravity free space at `(0, 0, 0) m and (30, 0, 0) m` respectively. Particle A is projected with a velocity `(5hat i + 10 hat j + 5 hat k) ms^-1,` while particle B is projected with a velocity `(10 hat i + 5 hat j + 5 hat k) ms^-1` simultaneously. Then,A. they will collide at `(10, 20, 10) m`B. they will collide at `(10, 10, 10) m`C. they will never collideD. they will collide at 2 s
Answer» Correct Answer - C For collision, `r_A=r_b` (at same instant) `:. (r_i+v_t)_A=(r_i+v_t)_B` `rArr (5 hati+10 hatj+5 hatk)t=30 hati+(10 hati+5 hatj+5 hatk)t` Equating the coefficients of x `5t=30+10t` `rArr t=-ve` So, they will never collide.

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