A 25.0 g object moving to the right at 24.0 cm/s overtakes and collides elastically with a 10.0 g object moving in the same direction at 15.0 cm/s. Find the velocity of each object after the collision. 25.0 g object ________ cm/s
10.0 g object _________ cm/s
10.0 g object _________ cm/s
-
m1 = 0.025 kg , u1 = 24 cm/s
m2 = 0.01 kg , u2 = 15 cm/s
using cons. of momentum u get :
0.025 (24) + 0.01 (15) = 0.025 v1 + 0.01 v2
=> 0.025 v1 + 0.01 v2 = 0.75
mult by 100 u get :
2.5 v1 + v2 = 75 ----------- (1)
since they collide elastically , Cr = 1 , so :
1 = (v2 - v1) / (u1 - u2)
=> v2 - v1 = 9 -------- (2)
=> v2 = 9 + v1
plug in 9 + v1 for v2 in (1) u get :
2.5 v1 + 9 + v1 = 75
hence v1 = 75-9 / 3.5 = 18.86 cm/s <<<<<<<<<<<
so v2 = 9 + v1 = 27.86 cm/s <<<<<<<<<<<<,
m2 = 0.01 kg , u2 = 15 cm/s
using cons. of momentum u get :
0.025 (24) + 0.01 (15) = 0.025 v1 + 0.01 v2
=> 0.025 v1 + 0.01 v2 = 0.75
mult by 100 u get :
2.5 v1 + v2 = 75 ----------- (1)
since they collide elastically , Cr = 1 , so :
1 = (v2 - v1) / (u1 - u2)
=> v2 - v1 = 9 -------- (2)
=> v2 = 9 + v1
plug in 9 + v1 for v2 in (1) u get :
2.5 v1 + 9 + v1 = 75
hence v1 = 75-9 / 3.5 = 18.86 cm/s <<<<<<<<<<<
so v2 = 9 + v1 = 27.86 cm/s <<<<<<<<<<<<,