# Search results

1. ### Low-Frequency Differentiator (need help with the calculus)

Homework Statement This is a low-frequency differentiator circuit. Vo(t) = -0.001*[dVi(t)/dt] Vi=0.5Vpk Frequency at 1kHz I am confused on how to apply calculus to this. My calculus is a little rusty but I am not use to seeing it in this applied forum. I only did calculus when it was in...
2. ### System of Equations (Matrices)

A jar contains nickels, dimes and quarters. There are 1469 coins in the jar totaling \$191.25. Assuming that the number of dimes is exactly twice that of the number of nickels, how many (each) nickels, dimes and quarters are there in the jar? We were suppose to be using matrices to solve this...
3. ### Power problem over time using calculus

A certain load is characterized by an instantaneous power that increases linearly from zero to 1 kW over a 3-hour period. Determine the total energy in (a) kWh and (b) joules. p(t) = [dw(t)] / dt W = F p(t)dt T2 is upper limit, T1 is lower limit. One of my problems is my calculus is...
4. ### Engineering Electrical Engineer vs Electrical Engineer Technologist

Ok I know there will be a life long battle between EE's and EET's. This thread is not about the Pros and Cons of the two programs. I am well aware of what each program has to offer and how they differ academically. I understand there will always be some people who look down on EET's. I...
5. ### Need help locating a project box with breadboard

I did some quick searches and couldn't find what I was looking for. I found plenty of project boxes, but I didn't find any project boxes with a breadboard combination for sale. I just need to make a circuit inside of a box using capacitors or inductors. Very simple but it has to look...
6. ### On which quadrants are each of the six inverse trig functions defined?

I have researched this area a little bit and now I am a little worried because three different websites have gave me three different answers. Some functions matched, but others didn't. My general concensus is inverse Sin= 1 and 4 quad inverse Cos= 1 and 2 quad inverse tan= 1 and 4 quad...
7. ### General Phase Shift Question

Find the phase shift of a function. Y=-5sin(x-pie/2) The Phase shift is (pie/2)/1 which equals to pie/2. The correct answer is units to the right though..which is where I need clarification on. My book said if phi is less than 0, it is too the left.. being -pie/2 wouldn't this...
8. ### A basic Theory Question (Electric Field Mapping)

If you reverse the polarities of the electrodes when you are "electric field mapping", wouldn't it show the same results on paper? Just the path it takes is reversed, but you would never know the difference wether it's going away or towards correct? I am diving into this "Electrical Field...
9. ### Metabolic Rate Problem

A weightlifter has a basal metabolic rate of 83.0 W. As he is working out, his metabolic rate increases by about 650 W. (a) How many hours does it take him to work off a 450 Calorie bagel if he stays in bed all day? answer: 6.3hours (b) How long does it take him if he's working out...

Ok first off, I got the answer so this should be simple to answer for someone who understands the theory. Sadly I must admit, the equation I used I have no real information behind it and I simply need to learn how it works and why I need to use it. First I will give you the problem: An...
11. ### Thermal Expansion Aluminium Problem

A brass ring of diameter 10.00 cm at 19.9°C is heated and slipped over an aluminum rod of diameter 10.01 cm at 19.9°C. Assume the average coefficients of linear expansion are constant. (a) To what temperature must the combination be cooled to separate the two metals? Brass=19 x 10^-6...
12. ### What is the centripetal acceleration of the Ferris wheel?

A 39.0 kg child takes a ride on a Ferris wheel that rotates four times each minute and has a diameter of 17.0 m. (a) What is the centripetal acceleration of the child? (b) What force (magnitude and direction) does the seat exert on the child at the lowest point of the ride? (c) What...
13. ### Basic Physics Problem

A certain light truck can go around a flat curve having a radius of 150 m with a maximum speed of 35.5 m/s. With what maximum speed can it go around a curve having a radius of 79.5 m? Answer is 25.8. I was trying to use the relationship of V=RW but I can't seem to figure out this simple...
14. ### Spring Problem, conservation of energy equation

Write the conservation of energy equation for this situation and solve it for the speed of the mass as it passes equilibrium. A horizontal spring attached to a wall has a force constant of 900 N/m. A block of mass 1.20 kg is attached to the spring and oscillates freely on a horizontal...
15. ### Simple Physics Problem (pushing a crate up a slope)

The coefficient of static friction between the m = 2.80 kg crate and the 35.0° incline of the figure below is 0.260. What minimum force must be applied to the crate perpendicular to the incline to prevent the crate from sliding down the incline? Attached is a picture. I broke down the...
16. ### Solving for X inside of a 3X3Matrix

Using cramers rule. the equation is. x,1,2 1,x,3 all set to equal -4x 0,1,2 I made my 2x2 matrix like this x|x,3| -1|1,3| +2|1,x| |1,2| |0,2| |0,1| eventually I ended up with x(2x-3)-1(2)+2(1)=-4x condensed it down to 2x^2-3x=-4x 2x^2+1x=0 x(x+1)=0 x=0...
17. ### System of equations problem

Homework Statement 4/x - 3/y=0 6/x +3/2y = 2 so I can make my own variables up. U= 4/x V= 3/y my problem is, how do I convert that on the second equation would 6/x turn into 1.5U and 3/2y turn into 1/V?
18. ### Simple inequalities question! I promise!

(x+2)/(x+4) greater or equal to 1. I got two different answers here. X is greater than 4. Or a interval notation (-Infinite, 4) - which doesnt make sense but wouldnt the correct answer just be X is greater than 4? which would mean (4, infinite)? Homework Equations...
19. ### Instantaneous Center of Rotation Help Needed

The figure below shows the piston-cylinder-crank arrangement in an internal combustion engine. When the piston is in the position shown in the figure, it has a downward speed of 900ft/min. I converted the 900ft/min to 180in/sec. I did the whole problem but I realized I used the wrong length...
20. ### Total Acceleration Question

Ok you have a disk that is originally rotating at a Wo=6rad/s. The Angular acceleration=4rad/s². Determine the magnitude of the total acceleration (combinaton of An and At) at point A just after 2 revolutions. The Circle is a 2ft Diameter circle with point A being 1.5ft distance from the...
21. ### Relationship between Rectilinear and Angular Motion

I am having a hard time understanding this concept... I understand Rectilinear motion consists of a line and Angular Motion is of a Angle. But I cant seem to understand how to use this for problem solving. I have two examples here that I will give and I have the answers but I cant seem to...
22. ### Can someone draw this diagram for me because I must be getting the wrong picture

Determine the maximum horizontal distance that a projectile will have at a height of 60 m above its origin if it is fired at an angle at 70degrees from the horizontal with a velocity of 50m/s
23. ### Projectile help needed!

A golfer wants to hit the ball a horizontal distance of 130M and 20M above his tee-off point, but wants the ball to land 10 M below his tee-off point. What is the balls Initial velocity? S= VoT+1/2AT² V= Vo+AT V²=Vo²+2AS So far I have broken up the graph into 3 Parts...from Point A...
24. ### Understanding Projectiles (Example Problem Given)

I dont know how to tackle projectiles and would like to have someone sort of show me what you look for in projectiles and how you normally tackle projectile problems. The golfer wants to hit the ball the same horizontal distance of 130M and 20M above his tee-off point as in Problem 10-32, but...
25. ### I cant solve a simple Acceleration/Deceleration rate of time problem.

A train with a maximum speed of 105km/h has an acceleration rate of 0.25m/s² and a deceleration rate of 0.7 m/s². Determine the minimum running time between stations 7km apart, if it stops at all stations. We are using the basic kinematics equations. S= VoT + 1/2aT² V=Vo +aT V² = Vo²...
26. ### Determine the Acceleration

The ball of a pinball machine is accelerated from rest to 11in/s in a distance of 4in. Determine the acceleration of the ball V=Vo +at A= Change of Velocity/ Change of Time The answer is 15.1 in/s^2 The time the pinball traveled was 4inches/11in - .36sec I cant seem to get...
27. ### Locate the Centriod of a Line Problem

I am trying to locate the centriod of a line and I am not getting to the end. The answer the book gives is Xbar= 5.74 and Ybar= 1.28 I am getting confused on where they are trying to call out the dimensions from what datum. Total line length is 18. L5 = ybar= 2.5 xbar= 0 L8=...
28. ### Solving a Truss Problem.

ok this is a basic truss problem and I have to solve every member in the truss(see picture) Basically I started off solving my reaction forces...For the bottom left Pin, i got 8kips goin left, and 9kips acting down...for the bottom right roller I got 9kips acting up. So after working my...
29. ### Statics/Physics Problem!

Knowing that friction equals 0.2 at all surfaces of contact, determine the magnitude of the force P required to move the 40kg plate B to the left. (Neglect Pulley Friction) This is a statics problem asking how much force will it take to move block B which is 40kg...the problem is it has...