Science Lesson 81 – Newton’s laws of Physics

Today I learned about Newton’s first three laws of physics. In the first video I learned about Newton”s first, second, and third laws of physics. His first law is that when one thing is in a state then the thing stays in the same state until some outer force interacts with it. This means that if a ball is rolling then it keeps rolling until something interacts with it and/or stops it, like gravity, friction, the ground, etc. In the end, outer space is the best example of Newton’s law of inertia because there is not as much sources of friction or gravity. This is shown with a baseball and a pitcher. If the pitcher throws the ball lightly, it falls back down and doesn’t go very far. This is not true when he throws it harder, and it goes farther, but it still falls down. If he throws it really, really hard, and the trajectory was correct, then it could go into space and start orbiting until the few atoms it meets slow it down enough for gravity to take it back down to earth. The point is, friction and gravity are the main things to slow objects down. The same physics for the ball apply to the capsule on the end of a rocket and that when the boosters ignite, it’s the same as the pitcher. The second stage is the few atoms that the ball meets, and then the capsule and ball can both go into orbit. Afterwards, the weight forces the ball and capsule down to the earth after slowing down and gravity pulls them. Then friction kicks in and they can disintegrate if they’re not protected correctly, and this is because of the heating caused by friction on the object’s surface from the oxygen molecules in the air. Newton’s second law is that to cause an object to be caused to move force must be applied and the more force applied, the greater the speed of the object will be and the greater the mass means the more acceleration and force is needed to move that object. In short, Weight x mass = Acceleration. This also relates to Newton’s first law because the more acceleration the object has the easier it is to move because of inertia. His third law is that for every action there is an equal and opposite reaction like a bouncy ball and the floor. If you bounce a ball on the floor, it bounces because the ball’s hitting the floor creates pressure on the floor and this is the action. But remember, “for each action there is an equal and opposite reaction,” so the floor releases the pressure on the ball, making the ball spring back up, which we see as bouncing. Those are Newton’s laws.

Science Lesson 33 – Cooking Food

Food can be cooked in many ways, like Grilling, Broiling, Baking, Boiling, Simmering, Steaming, Pan-frying, and Sauteing, and three different ways that heat can get around, eg. Conduction, Convention, and Radiation.

450495605_1280x760Conduction is a form of heat transfer that requires physical contact and a conductor to hold the heat electrons.  Convection is another form that requires a fluid or gas, and it traverses (circulates) the water/gas.  Then there’s the Radiation way of transmitting heat.  Radiation is where electromagnetic-spectrumthe heat travels far  and fast because it is a radio wave, which is how a microwave works.

500px-convectioncells-svg Heating food changes the flavor, aroma, and texture because the molecule structure is changed.  First, the heat is transferred to the food, exciting the molecules and/or atoms, so they vibrate.  Then the molecules split up, and they play somewhat like musical chairs, where they all scramble to get into position in the new structure, or “chair”.  They then bond in that structure, and that structure is the altered version of the old one, and therefore it changes the characteristics of the food.  Here, I’ll give an example: a potato.  When you bake a potato, it becomes wrinkly and brown, and the flesh (inside of the potato) turns dry and interesting-tasting.  That’s because of the molecule structure changing!