You are in a train traveling on a horizontal track and notice that a piece of luggage on the floor starts to accelerate directly toward the rear of the train. From this observation, you can conclude that this train is

Unpolarized light falls on two polarizer sheets whose transmission axes are at right angles. a third polarizer is placed between the first two so that its axis makes a 52-degree angle with the axis of the first polarizer. a) what fraction of the incident light intensity is transmitted through the first polaroid? b) what fraction of the incident light intensity is transmitted through the second polaroid? c) what is the angle of polarization of the light that enters the third polaroid? d) what fraction of the incident light intensity is transmitted through the third polaroid. e) what happens if the middle polaroid is removed?

What is special about a dc circuit ?

What is the speed of an object at a given moment?