Recent content by jablonsky27

the relativity principle states that all physical phenomena have the same form in all inertial reference frames. applying the galilean transformation to light and any inertial frame results in an incompatibility. similarly, doesn't applying the galilean transformation to sound also result in...

Hi, I'm reading up on special relativity and it is pointed out that the galilean transformation dictates that if a light source were moving at velocity v wrt to an observer in another inertial frame of reference, then this observer would calculate the speed of light to be either (c-v) or...

Thanks..

Andrew, Cleonis, To make sure I got this right, let me try to put into words my understanding... Observer A is inside the train. He does 0.5 J work to increase the speed of the block by 1 m/s. Observer B on the ground observes the energy put in by A also as 0.5 J. This breaks down as...

Here you re turning my question into a conservation of energy verification. That was not what I was trying to put forward. What I meant was this, 1. On the ground, if I get a block of mass 1 kg going at 1 m/s, I would have spent 0.5 Nm energy 2. Now, I get on a train which itself moves at...

Might be hijacking the thread, but I have a query here which struck me while reading Cleonis' post . Suppose a body of 1 kg mass rests on the ground. To get it going at 1 m/s I have to expend energy 1/2*1*(1^2) = 0.5 Nm. Suppose, the same body and me are on a train moving in a straight line...

I think that the distance the handbook refers to is the distance between the fire engine moving at 60mph and another vehicle(say a car) that's traveling at roughly the same speed in front of it which needs to get out of the fire engines way. If you are stationary, then you can hear the fire...

It depends which part of the motion is important for you. I mean depends on the situation. For your rocket example, if I am interested in the motion after the first stage boosters have been exhausted, my initial velocity will not be zero.

The hand;e/piston won't bounce back all the way up because even after you let go of it, its weight will still be acting on the air. So its still very very slightly compressed. This certainly isn't true - air doesn't combust. Perhaps he was talkinga bout a diesel engine and you misunderstood...

Power dissipated is proportional to resistance. So if you plot the two, should be a straight line.

If its not friction between tyres and the road, it ll be friction between the tyre and something between the tyre and the road.. In any case, that friction too will be independent of area..

Why does softer rubber grip better? If thicker tyres are made of softer rubber, then won't the diameter of the tyres reduce faster? So how does having more rubber make up for greater wear and tear?

Friction between 2 surfaces is independent of the area of contact and depends only on the nature of the two materials right? Then why do thicker car tyres give better grip?

looks to me like R1, R2, R3 are in parallel and the pot. difference between A and B is that provided by the battery.

hi, the \tau in the formula doesn't determine the steady-state value of current. it only decides how soon the current will reach its steady state value. if R=0 then the current will be big in only a purely resistive circuit. What you have is a resistive and inductive circuit. so if R=0, then...