Skip to main content

Snow Day Blog! Conservation of Momentum


To perfectly demonstrate conservation of momentum, my group decided to utilize exercise balls we had at our house. The medicine ball had a mass of 4 kg and the volleyball had a mass of .281 kg. In our experiment, we had the volleyball rest on the patio 1 meter in front of the medicine ball. While the volleyball was at rest, my sister gave the medicine ball a healthy push and let physics do its thing. Using Vernier Logger Pro, I recorded the video, analyzing it to show the conservation of momentum between this collision

 Collisions between objects are governed by laws of momentum and energy. When a collision occurs in an isolated system, the total momentum of the system of objects is conserved. Provided that there are no net external forces acting upon the objects, the momentum of all objects before the collision equals the momentum of all objects after the collision. If there are only two objects involved in the collision, then the momentum lost by one object equals the momentum gained by the other object.
Above is the video showing Bella pushing the 4 kg medicine ball. As you can see in the video, once the medicine ball collides with the volleyball, they both appear to move with the same velocity in the same direction. To see if this is true, we began to plug data points and analyse the video using Logger

We were able to find the velocity of the medicine ball before the collision by finding the line of best fit once all the points were plotted. The velocity was 0.94 m/s 

Medicine Ball before the Collision:
V: 0.94 m/s
M: 4 kg
P = (M)(V)
p= (4)(0.94) 
momentum = 3.76 kg m/s

Volleyball before the Collision:
V: 0 m/s
M: .281 kg 
momentum = 0 kg m/s 

Medicine Ball/Volleyball System after collision
V: 0.73 m/s
M: (m1+m2) = 4.281 kg
momentum= 3.125 kg m/s

As important point to remember is that momentum is always conserved while energy is lost through various means.

Calculating the Energy:
Initial KE of Medicine ball = (.5)mv^2 = (.5)(4)(0.94)^2 = 1.767 J
The volleyball had no KE because it was not moving before the collision 

Final KE of the system after the collision = (.5)(m1+m2)vf^2 = (.5)(4.281)(0.73)^2 = 1.141 J

Upon final analysis, can evaluated that this collision was in fact an inelastic collision; energy is lost in the collision yet momentum is conserved

As you can see, a small amount of energy is lost during this collision. There was a loss of 0.626 J 


Comments

Post a Comment

Popular posts from this blog

Physics of Black Holes...Or Lack Thereof

Isabella Jacavone To comprehend how the universe works, we must dwell into the most basic building blocks of existence; matter, energy, space, and time. NASA's  Physics of the Cosmos program involves cosmology, astrophysics, and fundamental physics intended to answer questions about the elusiveness of complex concepts such as black holes, neutron stars, dark energy, and gravitational waves. In this blog post, I'd like to elaborate on a subject that is very intriguing  to me; Black holes. And more specifically, what would happen if we got near one. A black hole is anything but a hole, but rather an immense amount of matter compacted into an extremely small area. A black hole is caused when, hypothetically, a star four times more massive than our sun collapses into a sphere no bigger than 600 square km. To put that in perspective, that's about the size of New York City. B lack holes were predicted by Einstein's theory of general relativity, which showed that when a...
Post a Comment
Read more

Aerodynamics of a Golf Ball

One may wonder how a small golf ball can travel at incredibly high speeds for such long distances.  While the swing of the club is a major component, the structure of the golf ball is quite important.  Unlike a baseball or tennis ball, a golf ball has dimples all over it (usually 336 dimples).  These dimples allow the golf ball to travel without facing much air resistance.  This diagram shows how air travels around the golf ball. The dimples on the golf ball also prevent drag that would occur in the wake region, resulting in further distance.  Also due to the contact with the club during the swing, the golf ball has backspin during its entire flight.  This diagram shows the motion of the golf ball mid flight with the lift force of F. There are hundreds of different types of golf balls that a player can choose.  Some show little affect to a player's game while others can alter their performance completely.  Personally, I prefer Callaway Supers...
Post a Comment
Read more

What Would Happen if Everyone in the World Jumped at Once?

Hypothetical and far out questions are what create great physicists and allow for us to discover and test things that have never been thought of before. Even as kids, we let our minds wander and ask questions that we never knew could be proved or disproved by physics. One question that I, as a young questioning child, and many other highly regarded physicists ask is simple; what would happen if every single person got together and jumped at once? This situation is completely unlikely to ever happen, so the only way we could ever know what would happen is through physics. Okay, so lets set the scene. Everyone, all 7 billion people, could fit into an area the size of Rhode Island, so lets assume that everyone did  travel to the smallest state in the US.  Finally, in unison, all 7 billion people jump. The push against the earth doesn't affect the earth at all, considering the Earth outweighs everyone by a factor of a mere 10 trillion. Even if the Earth were rigid and responde...
Post a Comment
Read more