Circular Motion Barbie is whirled in a horizontal circle on a 1.0 meter long string, such that the string makes a 10.° angle with the horizontal. Calculate Barbie's tangential speed

Please explain how to do it

What is the internal energy of 4.00 mol of diatomic nitrogen gas n2 at 455k

Suppose you have three polarizing filters, with the second at an angle of 42∘ to the first and the third at an angle of 90∘ to the first. by what perfect will the original intensity of unpolarized light be reduced to after passing through all three filters?

Unpolarized light of intensity i_0=750w/m^2 is incident upon two polarizers. after passing through both polarizers the intensity is i_2=280w/m^2. (a) what is the intensity of the light after it passes through the first polarizer in w/m^2? (b) write an equation for the angle between the polarizers in terms of the initial (i_0) and final (i_2) intensities. (c) find the angle between the polarizers in degrees.