Two particles having position vectors vec(r_1) = (3hati +5hatj) m and vec(r_2) =(-5hati-3hatj) m are moving with velocities vec(v_1) = (4hati +3hatj)ms^(-1) and vec(v_2) = (a hati + 7 hatj) ms^(-1). If they collide after 2 seconds, the value of a is

Two particles having position vectors vec(r_1) = (3hati +5hatj) m and

1.	Two particles having position vectors vec(r_1) = (3hati +5hatj) m and vec(r_2) =(-5hati-3hatj) m are moving with velocities vec(v_1) = (4hati +3hatj)ms^(-1) and vec(v_2) = (a hati + 7 hatj) ms^(-1). If they collide after 2 seconds, the value of a is
Answer» 2 4 6 8 Solution :Here, `vec(r_1) = (3hati + 5hatj) m, vec(r_2) = (-5 hati - 3hatj) m`, `vecv_1 = (4hati + 3 hatj) MS^(-1), vec(v_2) = (a hati + 7 hatj) ms^(-1)` `:. DELTA vec(r) = vec(r_1) - vec(r_2) = (3 hati + 5 hatj) - (5hati - 3hatj)= (8 hati + 8 hatj) m` and `Delta vecv = vec(v_2) - vec(v_1) = (a - 4) hati + 4hatj` But `Delta vec(v) = (Delta vecv)/(Delta t) :. (a - 4) hati+ 4hatj = ((8 hati + 8 hatJ))/(2)` On SOLVING , we get `a = 8`