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Andrew W
How to find amount of water vapor present in gram moles? basic thermodynamics problem...?
I found (a) the volume to be 1.08 m^3. But I have no idea how to solve (b) and it's driving me to insanity. Please help!
2 AnswersEngineering6 years agoIs the magnetic field always perpendicular to velocity of a positively charged particle?
When using the RHR, is the above always true? For example, if the magnetic field is pointing towards the page (so my fingers are pointing away from my body) does this mean that a positively charged particle will always deflect to the left? Or is it possible for a particle to deflect towards the page as well?
I just need clarification.
1 AnswerPhysics7 years agoHow to solve IVP ODE (dy/dx) = 4y - y^3 with y(0) = 1 ?
1 AnswerMathematics7 years agoHow to calculate torque on a grid. Am I doing this right?
So on a grid I want to calculate the magnitude of net torque with respect to point 0. Let's assume I have a vector acting on a point at r = (3i + 2j). The vector acting on the particle is F1 = 10 N at an angle of 30 degrees with respect to the x axis.
So would the torque of F1 be
T(F1) = (3i + 2j) x (10cos(30)i + 10sin(30)j)
or
T(F1) = (3i + 2j) x 10sin(30)?
1 AnswerEngineering7 years ago
Need help calculating vector angular momentum and torque due to an external force?
I'm not exactly sure what formulas to use here. Any help would be appreciated.
1 AnswerPhysics7 years ago
Block moves over smooth and rough surface into a spring, find max dist spring is compressed. Also kinetic energy and centripetal accel?
I have no idea how to do problem #3. I'm currently working on the next two which look pretty easy but I still want to check to make sure I'm getting the correct answers (since no answer key). I'm studying for an exam for tomorrow.
(Also your help was much appreciated, NCS, with my previous question in case you help me again.)
1 AnswerPhysics7 years ago
Need help with calculating work done by friction and work done by weight of a block, as well as max weight for a system to be in equilibrium?
For the first problem, how would the formulas for work done be different from each other for parts a) and b)? And acceleration can be found by Fnet = ma so a = Fnet/m right?
And for the second problem, I'm not exactly sure what I should be doing with that 45 degree angle...
1 AnswerPhysics7 years ago
Two forces act on a particle with mass that is initially at rest. What are the components of the particle's velocity at t = 10 s? And more?
Sorry, but there is a lot more to this problem. It's supposed to be a mix of laws in motion and review but I'm confused about which equations to use for it.
It is problem #15 in the picture. I drew the picture and calculated the magnitudes of the forces acting on the particle but I'm lost after that.
1 AnswerPhysics7 years ago
Not sure how to approach this "simple" problem (picture).?
I'm guessing I'll have to find the equations for x and y and use those to find what x(1) and y(1) are and then use those to find the magnitude and direction of the resultant vector. I'm working on the solution like this for now but I want to make sure that is the correct way to approach this problem (for step 1 at least).
1 AnswerPhysics7 years agoThe equations of motion for a particle are given by: x(t) = 4t and y(t) = 8t^2 + 2. Find the following?
(a) the magnitude and direction of the vector position for t = 2 seconds.
(b) the average vector velocity between 0 and 2 seconds.
(c) the magnitude and direction of the instantaneous vector acceleration for t = 4 seconds.
I'm not sure where to begin because there are two equations instead of just one like I'm used to. How do I start this problem?
3 AnswersPhysics7 years agoFind the general solution of this 2nd order linear ODE: (t^2)y"(t) - 5ty'(t) + 9y(t) = 0?
(t^2)y"(t) - 5ty'(t) + 9y(t) = 0
Is it even linear if the terms are multiplied like that? I want to know if I'm allowed to solve this with the method of undetermined coefficients?
1 AnswerMathematics7 years agoHow to solve this first order ODE? Very confusing, I have a picture (imgur)?
http://i.imgur.com/kos6znr.png
I don't think it's separable. Is it an exact equation? I'm trying that right now.
1 AnswerMathematics7 years agoA 1600 kg white sedan going 70 mph is involved in a T-bone collision with a 1000 kg red coupe traveling at?
A 1600 kg white sedan going 70 mph is involved in a T-bone collision with a 1000 kg red coupe traveling at 35 mph. The collision is completely inelastic and lasts for 0.10 seconds. Assume that the sedan is going in the negative x direction and the coupe is traveling in the positive y direction immediately before they collide. All masses above include any passengers and cargo.
a) What is the velocity (magnitude and direction) of the wreckage immediately after the collision, in mph?
b) What is the magnitude of the average force experienced by a 80 kg dummy in the sedan during the collision, in pounds? (You may assume that the final velocity of the dummy is the same as the rest of the wreckage.)
c) How much kinetic energy was lost by the cars (including all passengers and cargo) in the collision, in Joules?
1 AnswerPhysics7 years agoFind an expression for the maximum height yMAX the block goes.?
A block of mass m is pushed against a spring with negligible mass, and force constant k, compressing it an amount d1. After the block is released, it moves along a horizontal surface and then up a frictionless incline (the angle doesn't matter). The horizontal surface is also frictionless, except for a small rough patch of length d2 where the kinetic friction coefficient is uk (mu-sub-k). Find an expression for the maximum height yMAX (y-sub-MAX) the block goes.
I used the equation (1/2)kx^2 = mgLsin(theta) and substituted d1 for x and yMAX for L to get yMAX = [ (1/2)k(d1)^2 ]/[ mgsin(theta) ] but I don't think that's right. Help? I'm not sure where uk and d2 are supposed to play a role.
1 AnswerPhysics7 years agoSolve for the particular solution: y' = [e^(-y)]/[t+1] where y(0) = 0?
This is differential equations, how do I get the particular solution?
2 AnswersMathematics7 years agoGiven is the following circuit. What is the current I?
http://i.imgur.com/irjolvW.png
I can't figure out no matter what I try. No one gives a direct answer. I'm trying to study for a quiz. This is really stressing me out. Please help. I've tried applying KVL. Apparently I'm doing it wrong but no one tells me what I should do differently. **** me.
6 AnswersEngineering7 years agoWhat is the frequency of the sinusoidal wave?
The horizontal sweep rate of an oscilloscope (scope) is set to 0.1 millisecs/division. The scope screen shows a sinusoidal wave that goes through 2 cycles in 5 divisions. What is the frequency in Hz of the sinusoidal wave?
I was thinking 1 cycle in 2.5 divisions, so 2.5 div * 0.1 millisecs/div = 0.25 Hz. I'm not sure, though. Help?
3 AnswersEngineering7 years agoConstruct a graph corresponding to the stone's vertical displacement, y(t).?
A stone is thrown upward from the edge of a cliff, reaches its maximum height, and then falls down into the valley below. A motion diagram for this situation is given(Figure 1) , beginning the instant the stone leaves the thrower’s hand. Construct the corresponding motion graphs taking the acceleration due to gravity as exactly 10 m/(s^2) . Ignore air resistance. In all three motion graphs, the unit of time is in seconds and the unit of displacement is in meters. In plotting the points, round-off the coordinate values to the nearest integer.
Here is the figure and solution: http://i.imgur.com/YLhrpb4.png
The solution does not say what the coordinates are at each point so I'm REALLY REALLY REALLY confused how the **** they got that answer. Can someone please help me?!
3 AnswersPhysics7 years ago
