# ally_vanacker

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## Blog Entries posted by ally_vanacker

The highest a rabbit has ever jumped is 99.5cm in Denver on June 28th, 1997. to convert that into meters the measurement would be .995cm. from this information I gathered I also know that at the moment the bunny began to jump the initial velocity was 0m/s. also, since the bunny jumped on Earth I know its vertical acceleration had to be 9.81m/s^2 due to gravity. From all this information I can find how long the rabbit was in the air for. By using my three variables, I can use the d=vit+1/2at^2. Because initial velocity is 0 I can get rid of vit and make the equation equal to time since that it was I am solving for. My new equation to get time is t=2d/a all under a radical. Next, I substitute my three variables- initial velocity, distance, and acceleration, with the numbers a units and plug this into my calculator to get 0.45 seconds. Since the rabbit went a distance of .995cm up and had to come back down, I have to multiply the time by two. This leads my final result of the world record rabbit hop to be .9 seconds in the air!
On the show The Big Bang Theory, Sheldon goes to a Halloween party and dresses as the Doppler effect. he explains his costume to people by giving them the definition "its the apparent change in the frequency of a wave caused by the relative motion between the source of the wave and the observer". throughout the episode he also makes the noise of a car going by when people try to guess what his costume is. This noise he makes is a clear example of the Doppler effect because it sounds louder in the beginning and then fades away. This occurs when a siren of a police car or fire truck passes due to the Doppler effect.
Sound waves can help whales hear each other and communicate under water. Since the medium of these waves is water, the sound waves can travel much faster than humans talking on land. Medium is the main thing that can affect wave speed so whales are able to communicate quickly and other animals underwater also can too. Also, as the depth of the ocean increases as the whale goes further down the water gets colder which causes the speed to decrease. Temperature and pressure changing throughout the ocean can impact the sound waves of whales. A special case for these sound waves is the sound channel. the waves are able to travel thousands of miles and people have used technology to detect that they can hear sounds of whales many kilometers away in the ocean. Animals underwater must have a lot more fun communicating because the medium they are in!
While looking back on last week, our catapult taught me a lot about physics and also allowed me to use my problem solving skills. The catapult taught me about what angle to have the ball launched at, how adding more force to the catapult would make it go further, and also how height and speed affects the outcome of the catapult's results. But getting to the end result on Thursday was a result of loads of frustration and struggle. For example, Kylee, Grace and I had many trials and errors throughout our time together. At one point we spent an hour after creating it just trying to figure out how it would possibly ever catapult a softball. We had to be creative and make many different structures to get the ball to go forward. Also, we had to get creative in keeping two boxes of salt connected to the catapult without them falling off. After many slivers and moments of frustration and torture I am proud to say our catapult was as success.