Question

Two particles move along X-axis in the same direction with uniform velocities 8 m/s and 4 m/s. Initially the first particle is 21 m to the left of the origin and the second one is 7 m to the right of the origin. The two particles meet from the origin at a distance of m.​

Answer 1

Explanation:

particle 1

x = -21 + 8 t

particle 2

x = 7 + 4 t

so

-21 + 8 t = 7 + 4 t

4 t = 28

t = 4 seconds

x = 7 + 16 = 23

Damon

Aug 3, 2017

1 st particle

x+21=u¹t

21+x=8t

x=-21+8t....

2 nd particle

x-7=u²t

x=7+4t

equating 1st and 2 nd particles

-21+8t=7+4t

8t-4t=21-7

4t=28

t=28/4 = 7 sec

SUBSTITUTION

x=-21+8t

x=-21+8(7)

x= -21+56=35

(or)

x=7+4t

x=7+4(7)

x=7+28=35