Recent content by avsj

One way which I arrived at the right answer, was to start by setting Ff=Fg, and then setting Fn =Fc, but I am not sure if my reasoning for these directions is correct. In doing this, I got Fn= mg/u which ended up giving me the correct period. So Fn isn't always opposite in direction of Fg? IS it...

Homework Statement A 2.8m radius drum (cylinder) rotates such that a person does not fall when the "floor" falls away (imagine the person being pushed against the inside wall of the cylinder, with no bottom to the cylinder) If the coefficient of friction between the person and the wall is...

what do you mean work is equal to the integral over distance of force, what is the integral?

Homework Statement A force is exerted by a rope lifting a 2.0kg mass a vertical distance of 10m from the ground. A graphs shows F (N) vs d (m). THe F starts at 20 N and goes to 30 N in a straight line as d goes from 0 to 10m. What is the final speed of the box at 10m? Homework Equations...

Thanks Doc Al, seems simple in hindsight but you got me on the right track...:D Great help:)

Homework Statement Two cables are used to support a 24kg mass on 1.6 m long 8.0 kg unifrom horizontal beam. One cable is on each end of the beam and the mass is 0.6m from the right cable. What is the tension in the right cable? Homework Equations t=Fd Fg= mg The Attempt at a...

Homework Statement A proton traveling at a speed of 3.0 x 10^6 m/s travels through a magnetic field of strength 3.0 x 10^-3 T, making an angle of 45 degrees with the magnetic lines of force. What force acts on the proton? Homework Equations F = QvB The Attempt at a Solution I...

Homework Statement A roller coaster loop has a radius of 12 m. If the passengers are not to fall out at the top of the loop, what is the minium speed the car must have at the top. Homework Equations Fc = Fg-Fn Fc= mv^2/r Fg = mg The Attempt at a Solution I figure that for...

Oh I think i understand. The net force must equal the force of friction as it is moving so we use the Ff as the force. Thanks :D

The answer is 2.7 x 10^2 W. So if my Ff = 245, I need to subtract that from the horizontal force to get Fnet which I can then use to get W= Fd and to me it is obvious from there. But how do I find the horizontal force of moving the box? Thanks

Homework Statement A man slides a 100.0 kg box along the floor for a distance of 4.0m. If the coefficient of kinetic friction is 0.250, and the man does the job in 3.6s, what is his power output in watts? Homework Equations W=Fd P=W/t The Attempt at a Solution I don't know how...

Thanks Doc Al :D

Homework Statement A puck is let go on the top of a frictionless slope. The slope is length .74 m and 3.5 degrees above the horizontal. What is the acceleration and how long does it take the puck to go down the slope? Homework Equations Fnet=ma Fg=mg? The Attempt at a Solution...

Type 1- horizontal launch off cliff Type 2 - angled launch landing at same height as launch Type 2 - angled launch landing at different height as launch D is displacement And V is velocity and x and y are the horizontal and vertical components respectively.

Homework Statement For type 1, 2, or 3 projectiles, which of the following are constant? Dx, Dy, Vx, Vy Homework Equations The Attempt at a Solution I figure that the only one that is constant in all situations would be Vx because there is no acceleration in the x...