Skater in this situation, would have only changed So the force, the inwardįorce, the tension from the rope pulling on the Rink, they'll actually have the same speed. Very, very small frictions from the ice skating In whatever direction they were traveling Hold on to the rope, they'll keep going in circles. Now what is going to happen? Well, the skaterĪctually going to change. We're viewing all of this fromĪbove, and this right over here is the rope. Nailed to a stake in the ice skating rink right over there.

But imagine we're looking atĪn ice skating rink from above. If this does not make complete intuitive sense Videos on the intuition of centripetal acceleration Second statement is false, you could think about It does not take intoĪccount the direction. On a body will always impact the object's velocity. The object's velocity,' then this would be a true statement. Over here is 'speed.' If I had written 'impact The object's speed.' And the key word right Neither its speed nor itsĭirection will change. Particles that it's bumping into, absolute Going in some direction, and maybe it's deep space. Space with some velocity- so it has some speed On a body is zero, its velocity will not change.' This is absolutely true. Unbalanced force on an object will always change the Our everyday life is because they are beingĪcted on by unbalanced forces.' And statement four, 'An The object's speed.' Also an interesting statement. Unbalanced force on a body will always impact 'If the net force on a body is zero, its velocity

To do is figure out which of these statementsĪre actually true. Note that wavelengths and frequencies are properties that result from the wave aspect of light's behavior.īit about Newton's First Law, let's give ourselves In fact, the type of light we can see and that we think of as light, is really a rather small sliver in a much broader spectrum. One last thing, microwaves radiowaves, etc, are light except at much longer wavelengths (lower frequencies) than visible colors, while UV light, X-rays, and gamma rays are light with higher frequencies than visual light. So as you can see, the actual behavior of light is described by two branches of physics that didn't develop until the 20th century- quantum mechanics, and Einstein's theory of relativity. These sorts of problems related to the speed of light as well as what happens when something approaches the speed of light weren't really dealt with until Einstein formulated his Theory of Relativity. Therefore, light can't be modeled by Newton's 1st law of motion or any of the 3 laws of motion. You would think that if you were moving fast enough, light would appear to move slower next to you, but it never does! Also, as it turns out from Einstein's equations, Newton's laws of motion can't be used to describe anything at the speed of light or anything approaching such a speed. Things like photons were first modeled in detail by quantum mechanics and the whole idea that photons are at once both waves and particles also came out of quantum mechanics.Īnother thing Newton didn't know about was that light also always moves at the same speed regardless of your frame of reference, which come to think of it doesn't make sense. He wasn't aware of light's wave properties. Newton actually argued that light was made up of just particles. That alone can't be modeled by Newton's laws of motion and it's a pretty hard concept for anyone to really understand. Today we know light is made up of things that have no mass called photons that act as both waves and particles depending on how they are observed. For example, Newton discovered that white light is composed of all the colors in the visible spectrum (he actually didn't know anything about invisible light, such as radio waves, microwaves, X-rays, etc), but he had no good way of knowing the speed of light or what it is made up of. Light is a bit tricky and although Newton did a lot to advance our understanding of light and optics on a basic level, you'll find out that its actual behavior isn't described by Newtonian physics.

First law of motion