A 21.0 g marble sliding to the right at 21.1 cm/s overtakes and collides elastically with a 8.8 g marble moving in the same direction at 13.9 cm/s. After the collision, the 8.8 g marble moves to the right at 16.4 cm/s. Find the velocity of the 21.0 g marble after the collision.
2007-12-11 16:13:08 · 2 answers · asked by Kecin S 1 in Science & Mathematics ➔ Physics
Momentum is always conserved in collisions.
Initial momentum: ( 21.0 g ) ( 21.1 cm / s ) + ( 8.8 g ) ( 13.9 cm / s )
Final momentum: ( 21.0 g ) ( v ) + ( 8.8 g ) ( 16.4 cm / s )
Set these two expressions equal and solve for the unknown velocity.
2007-12-11 16:20:29 · answer #1 · answered by jgoulden 7 · 0⤊ 1⤋
Initial momentum = final momentum
mu + MU = mv + MV
21*21.1 + 8.8*13.9 = 21*v + 8.8*16.4
443.1 + 122.32 = 21v + 144.32
v = 20.052 m/s (towards right)
2007-12-11 21:05:02 · answer #2 · answered by gauravragtah 4 · 0⤊ 0⤋