# Search results

1. ### Java Java 'if' statements

Edit: Never mind guys, figured it out. I needed to use s.equals :) However, could someone explain to me why we can't use == on a technical level? I'm curious to know on a technical level. Hi guys Doing a bit of programming, and I'm not too sure why I'm not getting the expected results. Below...
2. ### Current versus dynamic force on linear actuators

G'day guys So I currently have a 2x 8" stoke 150lbs dynamic force actuators with a maximum current draw of 5A. The exact one is the FA-PO-150-12-XX in the link below: https://www.firgelliauto.com/products/feedback-rod-actuator The load I have on it causes the actuators to draw almost its'...
3. ### Calculating the Static Frictional Force of Nylon Bushings

Hi guys I'm looking to calculate the static frictional force for a hinge Below is a CAD image of the component I am testing. I am thinking of attaching a hook onto the plate as shown below, and continuously add weights at the end of the hook until the hinge begins to move. By multiplying...
4. ### Calculate the force to stop a train

Homework Statement [/B] Superman must stop a 120-km/hr train in 150 m to keep it from hitting a stalled car on the tracks. If the trains mass is 3.6 x 10^5 kg, how much force must he exert? Vi = 33 m/s (120 km/h) Vf = 0 m/s Displacement (Xf - Xi) = 150 m M = 3.6 x 10^5 kg Homework Equations...
5. ### Automotive Calculate the position for a linear acutator

Hi everyone! So I'm working on project where I have to design a hinge system for a hard lid that is fitted onto the back of a pickup truck. In this system, I will be using 2x linear actuator(s) that will need to lift a total weight of roughly 95kg. At the moment, I've got a selection of 600N...
6. ### Finding real numbers

Homework Statement Please see questions (c) and (e) on the attachement 2.Relevant Equations The Attempt at a Solution So long story short, these two questions were given out as a challenge in one of our Swedish lessons to see if we could remember our high school calculus, which I shamefully...
7. ### Calculating 3-Way Vectors

Homework Statement Homework Equations The Attempt at a Solution I can't remember what this method of calculation this is as it's been a while since I've done this. [/B] Could someone explain to me what I've done wrong in my calculations? The answer was 13.8N at 80 degrees.
8. ### Equilibrium and principle of moments

Homework Statement Homework Equations Torque = F x D Manticlockwise = Mclockwise The Attempt at a Solution From what I understand, the moment on left hand side of the pivot point needs to be equal to the moment on right hand side, therefore... (Fx.2)+(5x.14) = (7xd) My initial...
9. ### Simple Mechanical Questions

Homework Statement A) A circular rod is subjected to a bending moment of 315Nm. What is the minimum diameter of the rod required so that the maximum stress does not exceed 200N/mm2? B) If the Modulus of Elasticity for the material from which the rod is made of is 100kN/mm2, what radius...
10. ### Building a NOT gate

Is it possible to building one from using AND and OR gates, cause I've been trying and now I'm wondering if it's even possible
11. ### Fourier Transform using Modulation

Homework Statement Find the Fourier Transforms f1(t) = \frac{2}{3-it} f2(t) = \frac{2}{3-it}cos(t) Homework Equations F{H(t)et} = \frac{-1}{-1-it} F{f(t)cos(\omegat)} = \frac{1}{2}[F(\omega+\omega0+F(\omega-\omega0)] The Attempt at a Solution For the first question, my...
12. ### Engineering Using Thevenins therom to solve a simple circuits

Using Thevenins therom to solve a "simple" circuits Homework Statement The problems I am stuck on is problem two, figure 1 and figure 2. It's attached to this post. Homework Equations The Attempt at a Solution My initial attempt at solving for Rthev for figure 1 was that...
13. ### Identifying Gate Logic

Hi there I'm currently doing a digital fundamentals paper and I was wondering if anyone could identify a logic symbol on the spec sheet attached, and what's it used for. It's on page 4, and the logic symbol is a diamond that is surrounded by 4 traingles. Theres eight of them and it's near...
14. ### Finding the lifespan of a telescope mirror (probability question)

Homework Statement A telescope contains 3 large mirrors. The time (in years) until a single mirror fails has been investigated and we know that the probability that a mirror is still fully functional after t years is e^(-(t/10)^5 ) a) All mirrors must be working to take the most detailed...
15. ### Quality Control Charts

Hi all I'm having a bit of trouble trying to calculate the Upper and Lower Control Limit on R chart. The file "QualityIndex1180" contains the information from which I'm doing my calculations. Ob1, Ob2, and Ob3 are basically 3 samples that have been taken the first of 15 batches on some...
16. ### Conic Equation using a Quadratic Form

Homework Statement x12+x1x2+2x22=8 a) Write the equation using a quadratic form i.e. \underline{x}TA\underline{X}=8 b)Find the Matrix Q such that the transformation \underline{X}=Q\underline{Y} diagonalises A and reduces the quadratic form to standard form in terms of coordinates...