Spring board craziness

Watch this: 

Discuss how what you know about springs and energy conservation can help you explain why this is fake.

2008 world record for highest mototrcross jump

Redbull's no limits competition had Robbie Maddison jumping his motorcycle to the top of a 96 ft tall building. Check out the video here:

Here's a write up of the event - comparing it to the previous years' distance record:

Having broken the Guinness World Record for a motorcycle with a leap of 322
feet, 7.5 inches over the length of a football field during the 2007 Red
Bull New Year’s Eve event, Maddison had nowhere to go but up – more than
100 feet up. In front of a crowd of more than 300,000 New Year’s Eve
revelers chanting his name, the 27-year-old Aussie accelerated to 55 miles
per hour and launched his bike 105 feet high, landing on the top of the
96-foot-high and 40-foot-deep replica Arc de Triomphe in front of Paris Las
Vegas. After successfully landing on the top, Maddison swung his motorcycle
around and dropped a dizzying 60-plus feet to a landing ramp below, the
immense force of the impact lacerating his left hand, which was sutured at
a local hospital. Maddison’s impressive resume, in addition to his
record-breaking distance jumps, includes a very successful freestyle
motocross career.

“I just cheated death again,” said Maddison. “I’m ready to live another day
and am extremely excited to see what 2009 holds for me. The risk level of
my jumps was extremely high, and although I was confident in my abilities
and preparation, I knew there could have been major consequences, but that
is what pushing the limits is all about.”

So, if he was going 55 mph, what is the maximum height he could have reached? (Remember to use a conversion)

Why did he not reach that height?

How much of his energy was lost in reaching his maximum height?

Assuming the same ratio of energy loss, how fast would he be going when he hit the ramping the way down, 60feet below the top of the building?

Which law is it?

I am always amazed by how often I see newtons laws in action. Watch this video:

• Which law is being shown here? (Actually, you can see all three, but there is one that is more obvious that the others)
• See if you can identify at least 2 examples of each of newtons laws in this video!

Also, we can talk about torque here. 

• A large flatbed truck like this can have a mass of 3,000 kg mass. If the center of mass of the truck is 4 m in front of the axle, and the rear of the truck is 2.5 meters behind the truck, how much weight could you have centered over the back edge before tipping the truck up?
• When balanced like in #2, there are only 2 significant torques. What force provides the 3rd force to keep the system from rotating when the load is not that heavy?
• Can you draw a torque diagram for this when the truck is tilting up from the weight of the load?

Zip lines: tensions and torques

This year's Boo on Ballard had a Physics lesson built right in!! They had a zip line set up just begging to be analyzed in terms of forces, torques and spring constants!

Check out the video below: 

So, can you draw a diagram to show the tensions involved on a zip line?
What can you say about the torque applied by the hydraulic lifts in relation to the tension of the cables?
Think about the spring at the end. What considerations need to be made to make this safe?

Looking for some cash? Try science & engineering

Read the article linked below (they are the source of the images), but basically, science and engineering make up the top paying jobs out of all majors (top chart) and bachelor's degrees (bottom chart). Definitely worth knowing!

http://www.npr.org/blogs/money/2013/10/22/239698749/the-most-and-least-lucrative-college-majors-in-2-graphs?ft=1&f=

Whales and thermodynamics

So, you think whales take in water through their mouths and spew it out their blow holes? Wrong!!!
Check out this article on whales:
http://www.todayifoundout.com/index.php/2013/10/whales-dont-spray-water-blowholes/

This is a great example of thermodynamics at work. The air in the whale is both warm (due to the body heat of the whale) and is being compressed before being released (it has to push out the air - I imagine it has a diaphragm that causes additional pressure for expelling air). Warm air can hold a lot of water vapor. When the warm air is released, it mixes with cool air, which cannot hold as much water vapor, forming drops. It also reduces in pressure, which further cools the air as it expands.

The water drops in the spout from the whale are similar to when we breathe out in cold winter air and see clouds form, only theirs have more and larger droplets form.

Texas Sky Screamer

So, Eva (8) and I rode the 400 foot tall Texas Sky Screamer at six flags this week. Here's a picture of us -- she was pretty nervous.

So, this is an interesting circular motion problem, right here. Can you identify the forces acting on the riders? Try an assign an equation to each. 

What is really interesting is that the empty seats seem to be raised to about the same angle as the seats with people in them. Can you figure out why?