Question

1. change the masses and velocities to make your own new inelastic collision, then fill out the table below. (2 pts)

	mass	velocity before the collision	momentum before the collision	velocity after the collision	momentum after the collision
ball 2 (pink)
total momentum:

1. what happened to the velocity of ball 1 after they collided? what about ball 2? (answer for both of them!) (2 pts)
2. what happened to the momentum of ball 1 after they collided? what about ball 2? (answer for both of them!) (2 pts)
3. what happened to the total momentum after the collision? (1 pt)
4. keep playing with the simulation and write five complete sentences about your observations. (2 pts)

Explanation:

Step1: Define in - elastic collision

In an in - elastic collision, the two objects stick together after the collision. Let's assume Ball 1 has a mass $m_1 = 2\ kg$ and initial velocity $v_1 = 3\ m/s$, and Ball 2 has a mass $m_2=1\ kg$ and initial velocity $v_2 = 0\ m/s$.

Step2: Calculate initial momenta

The momentum of an object is given by $p = mv$. For Ball 1, $p_1=m_1v_1=2\times3 = 6\ kg\cdot m/s$. For Ball 2, $p_2=m_2v_2=1\times0 = 0\ kg\cdot m/s$.

Step3: Use conservation of momentum for final velocity

The total initial momentum $P_{total - initial}=p_1 + p_2=6+0 = 6\ kg\cdot m/s$. After the collision, the two balls stick together, so the total mass $M=m_1 + m_2=2 + 1=3\ kg$. By conservation of momentum $P_{total - initial}=P_{total - final}$, and since $P_{total - final}=Mv_{final}$, we have $v_{final}=\frac{P_{total - initial}}{M}=\frac{6}{3}=2\ m/s$.

	Mass	Velocity BEFORE the collision	Momentum BEFORE the collision	Velocity AFTER the collision	Momentum AFTER the collision
Ball 2 (pink)	$1\ kg$	$0\ m/s$	$0\ kg\cdot m/s$	$2\ m/s$	$2\ kg\cdot m/s$
Total Momentum:	-	-	$6\ kg\cdot m/s$	-	$6\ kg\cdot m/s$

Step4: Answer question 18

For Ball 1, its velocity decreased from $3\ m/s$ to $2\ m/s$ because some of its momentum was transferred to Ball 2 during the in - elastic collision. For Ball 2, its velocity increased from $0\ m/s$ to $2\ m/s$ as it gained momentum from Ball 1.

Step5: Answer question 19

For Ball 1, its momentum decreased from $6\ kg\cdot m/s$ to $4\ kg\cdot m/s$ as it shared momentum with Ball 2. For Ball 2, its momentum increased from $0\ kg\cdot m/s$ to $2\ kg\cdot m/s$ as it received momentum from Ball 1.

Step6: Answer question 20

The total momentum before and after the collision remained the same, $6\ kg\cdot m/s$. This is in accordance with the law of conservation of momentum which states that the total momentum of a closed system remains constant in the absence of external forces.

Step7: Answer question 21

1. In in - elastic collisions, the objects stick together after the collision.
2. The total momentum of the system is conserved throughout the collision.
3. The velocity of the object with initial non - zero velocity decreases after the collision.
4. The object with initial zero velocity gains a non - zero velocity after the collision.
5. The kinetic energy of the system is not conserved in in - elastic collisions as some energy is lost to other forms like heat and deformation.

Answer:

1. See the filled - in table above.
2. For Ball 1, the velocity decreased from $3\ m/s$ to $2\ m/s$. For Ball 2, the velocity increased from $0\ m/s$ to $2\ m/s$.
3. For Ball 1, the momentum decreased from $6\ kg\cdot m/s$ to $4\ kg\cdot m/s$. For Ball 2, the momentum increased from $0\ kg\cdot m/s$ to $2\ kg\cdot m/s$.
4. The total momentum remained the same at $6\ kg\cdot m/s$.
5. 1. In in - elastic collisions, the objects stick together after the collision.
6. The total momentum of the system is conserved throughout the collision.
7. The velocity of the object with initial non - zero velocity decreases after the collision.
8. The object with initial zero velocity gains a non - zero velocity after the collision.
9. The kinetic energy of the system is not conserved in in - elastic collisions as some energy is lost to other forms like heat and deformation.