Recent content by edziura

The soln is the sum of the two vectors (300 m/h E + 100m/h 30 deg N of E). Draw the first vector (arrow), then the second beginning with its tail at the tip of the first. Complete the triangle, then use triangle trigonometry to find the magnitude and direction of the third side. Alternatively...

"From this I took average velocity of the magnitude to be y/x to be -0.455/0.473" Not sure what this... Anyway, given the components vx and vy you have, the magnitude of this vector, and thus the average speed, is vav = sqrt((vx)^2 + (vy)^2)

the force acting on the particle is the magnetic portion of the Lorentz force; Newton's 2nd law; uniform circular motion Did you look up these topics in your textbook?

Theta is in radians, not degrees. Check which mode your calculator is in.

"I can visualize it, but can't put the steps togather to solve it. I know I have to find out what angle the position vector is pointing at, then solve for t. The distance from the center of the point probably won't vary with t right?" Find theta when t = 4, then use the transformation...

x = Vo + t(1/2)(a)(t^2) (1) Two unknowns: x and t V^2 = Vo^2 + 2ax (2) The term on the left is also (Vf)^2; in this problem, the plane is slowing down an Vf is 0. solve this equation for x, and substitute the result into (1) and solve for t. then you can solve for...

Yes, it does. What you've done is V (person w/res ship) +V (ship w/res to water) + V (water w/res to shore) = V (person w/res to shore)

"1) A particle of mass 7.7 x 10-8 kg and charge +6.8 μC is traveling due east. It enters perpendicularly a magnetic field whose magnitude is 2.5 T. After entering the field, the particle completes one-half of a circle and exits the field traveling due west. How much time does the particle spend...

That is correct. You need to write V (person w/res to ship). Now, based on how you did part a, how would you use this additional vector to find the person's velocity w/res to the shore?

We know the following: The spring force varies linearly from 9.00 kN to 0 kN. I'm writng this in kN for convenience, since kN / m^2 is kPa. Since the area of the piston is constant, and P = F / A, the pressure varies linearly also (as volume decreases) and so we can write a function P(V) = mV...

It says the spring force varies (decreases) linearly as the volume. You have two sets of (P,V) graph points, so you could write an equation of the form P = mV + c and use that to calculate the integral.

"I know that to calculate each component you need to have the value of the overall velocity - is that right?" Yes. "So, does that mean they are "related" to the overall velocity?" Yes.

The work done by the piston on the air is \int P dV You could write a linear equation for P as a fcn of V with the info you have, but of course geometrically this is just the area under the graph of P vs V, which in this case is trapezoidal in shape. Sketch the P-V trapezoid, calculate its...

Well, for part a you wrote V (ship w/res to water) + V (water w/res to shore) = V ship w/res to shore Assuming the info for part b is a velocity w/res to the ship, where in the equation do you think you should add the new vector?

Given the horizontal and vertical components of velocity, is there a way to calculate the magnitude of the overall velocity? Draw a velocity triangle. If there is, then the answer must be b.