Recent content by vrobins1

Homework Statement Three identical boxes sit on concrete floor, each box weighs 30 lbs (133 N). Each has a coefficient of static friction of 0.74 and a coefficient of dynamic friction of 0.64. Horizontal force of 80 N is applied to Box 1, horizontal force of 100 N is applied to Box 2, and...

Homework Statement A charged particle is observed to have a total energy of 0.642 MeV when it is moving at 0.700c. If this particle enters a linear accelerator and its speed is increased to 0.980c, what is the new value of the particle's total energy? Homework Equations Rest mass...

Homework Statement Monochromatic light, at normal incidence, strikes a thin film in air. If (lambda) denotes the wavelength in the film, what is the thinnest film in which he reflected light will be a maximum? Homework Equations 2d = (m+1/2)(lambda/nfilm) for minimal reflection and 2d =...

Homework Statement Unpolarized light is incident on a system of three polarizers. The second polarizer is oriented at an angle of 33.0° with respect to the first and the third is oriented at an angle of 45.0° with respect to the first. If the light that emerges from the system has an intensity...

Homework Statement Consider two straight conductors of length 1 m, each of them carrying a current of I = 2 A. If they are placed 1 m apart, what is the magnitude and direction of the force between these two conductors if there currents are a) in the same direction; b) in the opposite...

It was 182.8 and 357.2. Thanks!

This logically all makes sense to me, but I am still confused as to how to get the final answer. Does that mean that r = m?

Homework Statement An electron moves with speed 4.00 105 m/s in a uniform magnetic field of 3.2 T, pointing south. At one instant, the electron experiences an upward magnetic force of 1.00 10-14 N. In what possible directions might the electron be moving at that instant? Give your answers...

Homework Statement Find the magnitude of the current in each branch of the circuit shown below, in which B1 = 1.83 V. Specify the direction of each current. http://img183.imageshack.us/img183/6951/physics.gif I labeled + and - and drew the assumed currents, with I3 flowing to the right...

Would r be the distance from the sun to the earth?

I already tried to radius of the sun, so the radius of the Earth perhaps? The radius of the Earth = (6,378,100 meters).

Homework Statement The Sun emits electromagnetic waves (including light) equally in all directions. The intensity of the waves at the Earth's upper atmosphere is 1.5 kW/m2. At what rate does the Sun emit electromagnetic waves? (In other words, what is the power output?) The answer is...

I figured it out! I just used a more accurate number for my atmospheric pressure instead of simply 10000.

Homework Statement "At the surface of a freshwater lake the air pressure is 1.1 atm. At what depth under water in the lake is the water pressure 4.5 atm?" Homework Equations I used the equation Pgauge = Dgh The Attempt at a Solution I converted my atm to Pascals-->...

Homework Statement "A lid is put on a box that is 10 cm long, 16 cm wide, and 8.0 cm tall and the box is then evacuated until its inner pressure is 7.2e4 Pa." How much force is required to lift the lid at sea level? Homework Equations I know that I have to use P=F/A I changed my...