Skip to main content

Snow Day Blog 4


On this beautiful snow day, (well, a few days after the storm), I decided to take my dog outside to play his favorite game... frisbee!! But first, I had to convince him to help me with my physics blog. To start, I instructed my dog, Teddy, to sit and stay in one spot in the yard. He was VERY eager to get his frisbee, so I had to work fast. I was kneeling a few feet away from him with the frisbee, stationary in my hand, extended outward. This way, the video could capture Teddy running to grab his frisbee (at initial velocity 0). Using Logger Pro, I was able to solve for Teddy's initial velocity, and with these variables I was able to solve for the final velocity once Teddy and the frisbee were moving as one object. This scenario is known as a perfectly inelastic collision because the two objects (dog and frisbee) are eventually moving together as one.




Known Variables:
m1 = dog =22.73kg
 *converting 50lb to kg: 1kg = 2.2lb*
m2 = frisbee = .1814kg 
v1 = 2.65m/s

Now, using these known variables, m1, m2, v1, I used the formula: m1v1 + m2v2 = (m1+m2)vf, to solve for the final velocity of the system (dog + frisbee together).

The answer, 14.82m/s. Seems very fast for a dog running with his frisbee, no? This outcome could have been this extreme for a few reasons. First of all, the video stopped recording too soon once the dog grabbed the frisbee from my hand. This could have resulted in a faulty reading from Logger Pro, due to the absence of a few extra data points.

To find the amount of kinetic energy lost in the equation, I used the conservation of kinetic energy formula: 1/2(m)(v)^2 - KE = 1/2(m)(v)^2

1/2(22.73)(2.65)^2 - KE = 1/2(22.73 + .1814)(14.82)^2
79.811 - KE = 2516.042
KE lost in collision = 2436.231 J

After torturing my dog enough with physics homework, he finally got to enjoy some frisbee time :)



Comments

Popular posts from this blog

Physics of Sound Dampeners and Active Noise Cancellation

Physics of Sound Dampeners and Active Noise Cancellation Sound dampening foam panels in a recording studio. ANC headphones worn by pilots and/or passengers in consumer aviation aircraft.  Acoustic treatment of soundscapes has grown alongside the sound production industry. Whether through absorption panels, diffusors and cloud panels to treat a space or headphones placed directly over the ears of listeners, acoustic treatment comes in many forms. Environments are treated acoustically to absorb excess sound to prevent sound levels from crossing a threshold above which the desired goal cannot be had. Before getting into sound dampening, we must discuss sound. Sound is produced when an object vibrates (a form of oscillation) and temporarily displaces nearby air molecules causing a wave effect as the displaced molecules collide with their neighboring molecules. Sound waves are fluctuations in pressure as the initial displacement of molecules experiences collisions that in ...

Large Hadron Collider

The Large Hadron Collider (LHC) is the world’s largest and most powerful particle accelerator. The LHC is the largest machine in the world. It took thousands of scientists, engineers and technicians decades to plan and build, and it continues to operate at the very boundaries of scientific knowledge. It first started up on 10 September 2008, and remains the latest addition to CERN’s accelerator complex. The LHC consists of a 27-kilometre ring of superconducting magnets with a number of accelerating structures to boost the energy of the particles along the way. Map of LHC (located in Geneva, Switzerland) Thousands of magnets of different varieties and sizes are used to direct the beams around the accelerator.  Just prior to collision, another type of magnet is used to "squeeze" the particles closer together to increase the chances of collisions. The particles are so tiny that the task of making them collide is akin to firing two needles 10 kilometres apart with suc...

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...