Two masses of 20 and 10 kg are moving in the same direction and one directly behind the other. The 20-kg mass is behind and moving at 10m/s and the other is moving at 5m/s. The masses collide and after the collison, the 20kg mass moves at 6m/s find the after-collison velocity of the 10kg mass.
I can't find the formula for this problem
You need to apply principles: First, the conservation of momentum,
total momentum before collision = total momentum after collion.
20*10 + 10*5= 20*6 + 10*velocity
check that.
The formula you are referring to is the conservation of momentum. In this problem, we have two masses (20 kg and 10 kg) moving in the same direction. The total momentum of the system before the collision is equal to the total momentum after the collision.
The total momentum before the collision is given by the formula:
Total momentum before = mass1 * velocity1 + mass2 * velocity2
In this case, mass1 is 20 kg, velocity1 is 10 m/s, mass2 is 10 kg, and velocity2 is 5 m/s. Plugging in the values, we get:
Total momentum before = 20 kg * 10 m/s + 10 kg * 5 m/s
= 200 kg*m/s + 50 kg*m/s
= 250 kg*m/s
After the collision, the 20 kg mass moves at 6 m/s. We are asked to find the velocity of the 10 kg mass, denoted as velocity.
The total momentum after the collision is given by the formula:
Total momentum after = mass1 * velocity1 + mass2 * velocity
In this case, mass1 is still 20 kg, but velocity1 is now 6 m/s. We are looking for the velocity of mass2, which is denoted as velocity. Plugging in the values, we get:
Total momentum after = 20 kg * 6 m/s + 10 kg * velocity
= 120 kg*m/s + 10 kg * velocity
Since the total momentum before collision is equal to the total momentum after the collision, we can set up the equation:
Total momentum before = Total momentum after
250 kg*m/s = 120 kg*m/s + 10 kg * velocity
Now, we can solve for the velocity:
250 kg*m/s - 120 kg*m/s = 10 kg * velocity
130 kg*m/s = 10 kg * velocity
Dividing both sides by 10 kg, we get:
(130 kg*m/s) / 10 kg = velocity
13 m/s = velocity
Therefore, the after-collision velocity of the 10 kg mass is 13 m/s.