Two balls A and B are thrown simultaneously ,A vertically upwards with a speed of 20m/s from ground,and B vetically downwards from a height of 40 m with the same seed and along the same line of motion . At what points do the two balls collide ?
Answers
Answered by
0
Let the two balls meet at distance x from the ground after time t.
For ball A:
u = 20 m/s; g = 10 m/s2; h = x
using h = u t - (1/2) g t2
x = 20 t - 5 t2 -------------(1)
For ball B:
u = 0; g = 10 m/s2; h = 40 - x
using h = u t - (1/2) g t2
40 - x = 5 t2 -------------(2)
Using eq. (1) and (2)
40 - 20 t + 5 t2 = 5 t2
t = 2 s
From eq. (1), x = 20 m
For ball A:
u = 20 m/s; g = 10 m/s2; h = x
using h = u t - (1/2) g t2
x = 20 t - 5 t2 -------------(1)
For ball B:
u = 0; g = 10 m/s2; h = 40 - x
using h = u t - (1/2) g t2
40 - x = 5 t2 -------------(2)
Using eq. (1) and (2)
40 - 20 t + 5 t2 = 5 t2
t = 2 s
From eq. (1), x = 20 m
Similar questions