Recent content by blazeuofa

hmm I can't quite get the right answer. V=22.4L and avagadros # is the molecules in one mole. How do I piece this together?

Homework Statement Determine the number density of particles in a gas at STP (T=273, p=1atm) Homework Equations Answer is 2.68x1025 The Attempt at a Solution pV=nRT I don't really understand what the "number density of particles" means please help!

So for a time equal to 3 periods...\omega=2\pi/3=2.09 so T=2\pi/2.09=3.01s Please help I'm so lost :(

Homework Statement A mass on a spring undergoes simple harmonic motion with amplitude A. a) In a time equal to three periods, what is the magnitude of the displacement of the mass? b) In a time equal to three periods, what actual distance did it travel? Homework Equations The...

Homework Statement A 3kg ball moves at constant speed in a horizontal circle on the inside of a cone. The radius of the circle is 2m. Determine the magnitude of the normal force acting on the ball and the time required for the ball to complete exactly one circle. Assume that the surface of the...

Homework Statement A box has an intial speed of 10 m/s. It slide across a flat section and then up an incline. Use L=20m, \muk=.1, and \theta= 40 degrees. Note that I have not given you the mass. It will cancel out of all the equations in the end. a. Determine the speed of the box at the...

so Fx=Sin\theta and Fy=mg I know the answer is F=mg/sin \theta, but I thought you divide Fx by Fy? So why is the answer F=mg/sin \theta?

Homework Statement A box of mass (m) is held against a frictionless wall by a force of magnitude F at an angle \theta (above right). Determine F in terms of whatever variables are necessary. Similarly, determine the magnitude of the normal force (n) in terms of whatever variables are...

yeah i got it thanks

yeah i don't get how to do that though

Homework Statement A projectile is fired at a speed of 45 m/s at an angle of 40 degrees above horizontal. Determine the magnitude and direction of its velocity 4 seconds later. Homework Equations ax=0 ay=-g The Attempt at a Solution

what do you get when you square B?

yes that's what i mean. What would be the result of adding those? That's where I am stuck

Homework Statement Vector A = (2x-y)m and Vector B= (x+ay)m (a is alpha, m is meters) If |A+B|=5m, determine the possible values of a.Homework Equations The magnitude of A= sqrt 5 The Attempt at a Solution |A^2 + B^2|=5^2 |(2x-y)^2 + (x+ay)^2|= 5^2 |(2x-y)^2 + (x+ay)^2|= 25 I cannot figure...