Inertia- a property of matter by which it continues in its existing state of rest or uniform motion in a straight line unless that state is changed by an external force.
Alright, what inertia essentially boils down to is an object`s resistance to change. Meaning, that if an object is moving in any particular direction, the object in question will keep moving in that direction until it is acted on by some other force. Now, I can already hear someone shouting, “But Mike, I can push a chair across the floor and it will eventually come to a stop without anyone touching it.” This statement is correct, however there is in fact an outside force acting on the chair. That force is friction. In this case scenario, the friction between the wheels of the chair and the floor causes the chair to slow down and eventually come to a stop. Without friction, the chair would continue to travel in that direction forever.
Gyro comes form the Greek word guros meaning “a ring”. So, you could say this geek word comes form a Greek word….
So, what real world applications does inertia have? The best example I can think of is a bicycle. Bicycles by design have two wheels; one at the front and one at the back of the frame. When the wheels rotate they create inertia because they resist change in any direction. Most notably in the side-to-side direction, which allows the bike to stay upright while the rider, is riding it. This is also the reason why it is next to impossible to balance on a bike when it is not moving (for most people anyway). This effect is called gyroscopic* stabilization and it is made possible by inertia.
*When I say gyroscopic I mean gyro as in the gadget that balances on its own while spinning; as opposed to the delicious Greek sandwich.
Acceleration- rate of change of velocity per unit of time.
Alright, before everyone starts saying, “ Hey Mike, that`s not really a Nerd Word everyone knows the definition of acceleration,” Let me explain, even though this is a well known word, I think that it is a bit misunderstood. The most common misunderstanding is that acceleration means both speeding up and slowing down. How can this be? Well, as the abstract and some what confusing definition states, “ rate of change of velocity,” that means anytime the velocity* or speed changes acceleration occurs. Often times, slowing down is referred to as negative acceleration. Acceleration is one of the most commonly observed physical phenomena, the most common being gravity. Gravity by definition pulls things downward or toward the center of the earth. Moreover, when it is pulling something downward it is accelerating them at a rate of 32.2 ft/s2. This is referred to as the acceleration due to gravity and it has many applications including making snowboarding possible.
Lets take the typical downhill run and break it down. First, the rider starts to roll down the hill, as the rider gets further down the hill they begin pick up speed, they are accelerating. Then the course begins to flatten out and they are no longer accelerating because they are traveling at a constant speed. Finally, they hit a jump a begin to travel up hill; they begin to accelerate again, but because they are traveling uphill they are slowing down. Even though they are slowing down they are still accelerating because the speed at which they are traveling is changing. Then they fly into air while performing some mind- boggling trick, and then land. All the while utilizing acceleration in both directions.
Just like the massive amount of snow, we`ll keep ‘making science cool’
* velocity sounds cooler than speed
Friction-noun resistance that one object encounters when moving over another.
Friction is a term that many people have heard of before, but there is some misunderstanding of exactly how it applies in the real world. First of all, friction is resistance and not force. This simply means that friction is a measurement of the amount of resistance that an object is encountering. Furthermore, the amount of friction an object is encountering is said to be its coefficient. Giving meaning to the term coefficient of friction. So, the larger the coefficient of friction the greater the resistance the object is encountering. To put this into perspective, imagine a situation in which you are trying to train both a cat and a dog to fetch your newspaper. Even though you are trying to accomplish the same feat, you will experience a much greater amount of resistance from the cat than you will from the dog*.
Understanding friction is one of the key components in making a racecar go faster. If you are a loyal reader you will remember that when the car is in a turn, the friction between the tires and the pavement is what is keeping the car from flying off the track. However, friction can also work against you because friction creates drag and drag decreases the overall top speed of the car. So which is better grip or speed? Well, the answer that it depends on whether the you want the car to be fast in a straight line or fast through the corners. If there is too much friction or grip, the car will not accelerate to it`s top speed, however if there is not enough grip the car will not be able to stay on track through the corners creating spectacular screens of sliding (cool to watch, but not very fast). The challenge is finding balance, that mystical blend of corner grip and top speed, that is what sets the track records and wins races.
* I don`t know if I ever have seen a dog outside the movies that will fetch the newspaper for it`s owner.
The key to making a racecar go faster through the corners, keeping the most amount of the tire in contact with the track.
Merry Christmas, from all of us at Driving4Education and remember Science is fun!