Recent content by bopll

nevermind, i guess i did the calculations wrong. Can anyone confirm this setup at least?

right, this is definitely something that comes with experience. You'll notice patterns that will help you choose u. For this example, since you know you will get (something)x^2 when you take the derivative of (something)x^3, you know that the term with the x^3 will want to include u. You...

you're on the right track. This is a piecewise function, and in order for there to be a derivative at 1, the values for the derivatives AT 1 have to match from both sides... imagine a graph of the function. you have probably learned that there will not be a derivative if there is a cusp in...

Homework Statement A water tank is in the shape of a half cylinder sitting on its side (not its top or its bottom). Let the radius be 10 ft and let the side-lenth on the floor be 30 feet. What should be the water height, measured from the floor up, so that the water tank is half full...

i tried this also, maybe i made a calculation error...

okay, so if i have to use kinetic energy, does that need i need to find the mass of the car (1/2mv^2)? that doesn't seem right...

Homework Statement A car encounters an inclined plane Given- Weight of car in N (6500), velocity on the flat surface (22.5 m/s), power of the engine (78000), incline of the hill (8.1 degrees) Want to find- velocity on the hill (power and restistive forces remain constant) Homework Equations...

just a bump to this thread, wanting to verify: You set the K.E. and the U(spring) equal to each other i.e. (1/2)mv^2 = (1/2)kx^2 because of the conservation of energy? and this is why you don't need the force? EDIT: my problem is on a frictionless plane.

How do i mark a thread as solved?

ugh. my calculator was in radians. *facepalm*

that's what i did :-\ it came out to .3979 ish and that wasn't right...

sorry. the distance it's pushed up the hill.

Homework Statement An object is given an initial velocity of 3.0 m/s up a 20 degree incline. Mass= 22.3 kg and coefficient of kinetic friction is .93.Homework Equations W = (1/2)mv1^2-1/2mv0^2 W = Fdcos(u)The Attempt at a Solution So I added the forces together, mgsin(20) + .93mgcos(20)...