Impulse Can Change Momentum by Making an Object Go Slow
Remember: Impulse is defined as change in momentum, but it is also defined as force multiplied by time. In other words, if you want to change an object's momentum (usually velocity), you must exert a force on it over some time.
Just as you can change an object's momentum by speeding it up, you can also change its momentum by slowing it down. In order to slow an object down, you must exert a force on it over some time. For example, in the animation below, the car is slowed down because a force is exerted on the car over a period of time.
Click HERE if you are unable to view the animation below.
Now, if you want to really slow down a car a lot without exerting a huge force on the car (or on the riders it contains), you should exert that force on the car over a LONG period of time. You do the same thing subconsciously when you catch a baseball without a glove. You bring your hand back with the ball. Increasing the time the force acts on your hand DECREASES the force acting on it.
Just as you can change an object's momentum by speeding it up, you can also change its momentum by slowing it down. In order to slow an object down, you must exert a force on it over some time. For example, in the animation below, the car is slowed down because a force is exerted on the car over a period of time.
Click HERE if you are unable to view the animation below.
Now, if you want to really slow down a car a lot without exerting a huge force on the car (or on the riders it contains), you should exert that force on the car over a LONG period of time. You do the same thing subconsciously when you catch a baseball without a glove. You bring your hand back with the ball. Increasing the time the force acts on your hand DECREASES the force acting on it.
If you want to slow an object down WITHOUT exerting a large force on that object, you should exert a force on the object over a LONG time. This is what an airbag or a seat belt does. |
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