Tuesday, May 31, 2005
What causes the seasons?
Question:
What causes the seasons:
Hints:
If you had to give one reason it's because the earth is titlted 23.5 degrees relative to the ecliptic (the plane that the earth rotates around the sun in).
This causes two effects, one is that the sun is up for longer during the summer than it is in the winter. This gives the sun more time to heat the ground than in the winter. But this is not the most important reason.
The most important reason is that the sun is higher in the sky, and points down more directly. Imagine flashlight in your hand and you point it straight down to the ground. It makes a small, bright circle of light. If you tilt the flashlight it'll make a larger, duller oval of light. But the amount of energy is the same from the flashlight it's just spread over a bigger area.
Note also that the sun doesn't heat the air or the clouds (or very little) it heats the ground (or the water) and the ground heats the air.
What causes the seasons:
Hints:
- It's not because we are closer to the sun in the summer.
- There are two reasons it's warmer in the summer and both are caused by one other reason. (name all three for a bonus!)
If you had to give one reason it's because the earth is titlted 23.5 degrees relative to the ecliptic (the plane that the earth rotates around the sun in).
This causes two effects, one is that the sun is up for longer during the summer than it is in the winter. This gives the sun more time to heat the ground than in the winter. But this is not the most important reason.
The most important reason is that the sun is higher in the sky, and points down more directly. Imagine flashlight in your hand and you point it straight down to the ground. It makes a small, bright circle of light. If you tilt the flashlight it'll make a larger, duller oval of light. But the amount of energy is the same from the flashlight it's just spread over a bigger area.
Note also that the sun doesn't heat the air or the clouds (or very little) it heats the ground (or the water) and the ground heats the air.
Bus Ride
Question:
You are riding a bus, where's the best place sit on the bus for the most comfortable ride?
Hints:
I'd say that sitting in the middle should give you a more comfortable ride.
The reasoning is that if you are over the back wheel, say, you get the amplitude of the bumps over that wheel. If you are further back, you get the amplitude plus a bit more because of the lever effect. If you are in front of the back wheel you get less amplitude (lever again).
Unfortunately, both wheels are bouncing so the best you can do is average the two by being between them.
You are riding a bus, where's the best place sit on the bus for the most comfortable ride?
Hints:
- We're talking about the up and down (bumpy) part of the ride.
- We're asking is a seat near the front, middle, back or over one of the wheels is the best location.
I'd say that sitting in the middle should give you a more comfortable ride.
The reasoning is that if you are over the back wheel, say, you get the amplitude of the bumps over that wheel. If you are further back, you get the amplitude plus a bit more because of the lever effect. If you are in front of the back wheel you get less amplitude (lever again).
Unfortunately, both wheels are bouncing so the best you can do is average the two by being between them.
Transferring the Ransom
Question:
You kidnapped something or someone and they have agreed to give you the money. How do you transfer the money without getting caught?
Hints:
You kidnapped something or someone and they have agreed to give you the money. How do you transfer the money without getting caught?
Hints:
- You don't want the cops to be able to follow you
- Paris has a very complex sewer system
- One solution was to tell the cops how to wrap the money in a waterproof container. Then have them go to a phone.
- From that phone you are told to go to a street.
- Then you are told to throw the package in the sewer on that street corner.
- The water carries the package away, but the sewer system is so complex it is difficult for the cops to know where it'll go and where you'll picked it up.
- But you already tested it by throwing similar packages in the sewer and seeing where it comes out.
Intro
The basic idea of this blog is to record some dinner time questions for your kid(s). Relatively easy questions that make you think, that may have several answers.
