# Search results

1. ### Weird traffic controller

Hi, I got this instruction given: > For each of the following three scenarios, initially assume that the East-West traffic has had a green traffic light for a long time. 1) If a North-South car is detected then the traffic lights will cycle to green in that direction. The walk light will...
2. ### First order RC Circuit Table problem

Homework Statement Hi I got this problem and have to fill out this table. Homework Equations node analysis time constant = RC ic(t)= C dVc(t)/dt The Attempt at a Solution I got few answers which i worked it out. i (0-) = 0 Vc(0-) = 1.84 Vr(0-) = i (0-) *...
3. ### Thermodynamics !

Homework Statement A stove burner supplies heat to a pan at the rate of 1500 W. How long will it take to boil away 1.1 kg of water, once the water reaches its boiling point? Homework Equations q = mct The Attempt at a Solution heat transfer = 1500 W, m = 1.1 KG Tf = 100 [
4. ### Find the tension in the horizontal cable that supports the boom

Homework Statement A crane in a marble quarry is mounted on the rock walls of the quarry and is supporting a 2000 kg slab of marble as shown in the figure. The center of mass of the 900 kg boom is located one-third of the way from the pivot end of its 15-m length, as shown. Given...
5. ### Torque Problem Static equilibrium

Homework Statement Homework Equations How to do this question ?? The Attempt at a Solution I know sum of torque and force = 0 at fapplied i got torque = 25sin(45) * 3.8m = 67.18N .. But dont know what to do next !!!
6. ### Other Force problem

Other Force problem !!! Homework Statement Two forces act on a 3.1 kg mass, which undergoes acceleration a = 0.88 i - 0.28 j m/s2. If one of the forces is F1 = - 1.5 i - 3.0 j N, what is the other force? Homework Equations I don't know how to visualize this !!!! The Attempt at a...
7. ### K-Map Symbol.

Hi, below image. My teacher use symbol in K-MAP. But not sure how it uses. Myattempt : i got 0 0 0 0 0 0 1 1 0 0 1 1 0 1 1 0 --> Using his technique. Can somebody help me out ?
8. ### Why period is half ? Spring problem

Homework Statement A mass m slides along a frictionless horizontal surface at speed v initial. It strikes a spring of constant k attached to a rigid wall. After a completely elastic encounter with the spring, the mass heads back in the direction it came from. (a)In terms of k, m, and v...
9. ### How to Take the sum of moments

How to Take the sum of moments !!! Homework Statement Hi i am doing static equilibrium exercises in textbook. Homework Equations But I dont know how to find sum of moments at P when its come to angle. This is a drawing The Attempt at a Solution I have No idea !!! I was...
10. ### Aluminium Block immersed in water beaker

Homework Statement physical reasons for the relationship between weight change(100CC beaker with water and when you dip aluminum block in water ) and apparent loss in weight of the aluminium (Aluminium block weight using spring balance and when that block immersed in water) Homework...
11. ### Surface Area frictional force

Homework Statement does surface area to affect the values of coefficient µk? Homework Equations frictional force =µk * normal force The Attempt at a Solution I know that if mass is larger then the frictional force is higher( f= ma) but how about the surface area? does it affect...
12. ### Find i(t)

Homework Statement [Broken] Homework Equations impedence diagram, XL = ωL The Attempt at a Solution Ok i got XL = 47 ohm Then my phase angle is 88.8 degree. Then to find i(t) i have to add that angle to the function right?
13. ### How? Which Trig Identityis that?

How?? Which Trig Identityis that? Homework Statement [Broken] Homework Equations The Attempt at a Solution sin^2 = 1- cos^2 ??
14. ### Ok how do they got this ?

Homework Statement I am following book and they got this equation but i dont know how they got it ?? [Broken] Homework Equations The Attempt at a Solution I know they use kirchoff's voltage law but at which point they are choosing and how they are going and acquire this...
15. ### Impedance Problem

Homework Statement A circuit consists of a 50nF capacitor in series with a 47kΩ resistor. An AC voltage of 120Vrms at 350Hz is applied to the circuit. (a) Determine the current flowing through the circuit. (b) Sketch the impedance diagram for the circuit at this frequency. Homework...
16. ### Incident question - historical event with lack of ethics

incident question -- historical event with lack of ethics I have to Write a report outlining an historical event in which a lack of ethics has caused the injury or loss of life. You should discuss the issues with reference to the Engineers Australia code of ethics. i cant find any events...
17. ### RLC circuit

[Broken] This is my question 1. and this is my question 2. in a RLC series circuit show above are replaced following : R=500Ω L=0.4mH and C=100pF the circuit is connected to the terminals of an ac source with an rms voltage of 1V, and a variable frequency calculate the following A)...
18. ### Engineering Multisim rms current and voltage RLC Circuit

Trying to find rms current at resonance and rms voltage across each elements (resistor, inductor and capacitor) I got the answers but i want it do in multisim !! i got : R = 500 ohm L = 0.40mH C = 100pF The answer is rms current: 0.002A rms voltage: Vr = 1V Vc = 126.52 V Vl = 126.52 V...
19. ### Confusion RLC circuit

Homework Statement Hi i got this question ? [Broken] have to find Vr and VL so can i use this formula : VR = IR VL = I * XL??? confuse ?? need help ?? am i on right track?
20. ### Low and High Pass Filter

Got excel spreadsheet. in my excel worksheet "4" i plot bode plot for low and high pass. Our lab experiement aim was measure two set of data and identify which one is low pass and which one is highpass filter. But as soon as I am trying to put lograitham graph it is not allow me ? I...
21. ### Voltage across a capacitor?

Lets say if i got RC series circuit. If i increase the voltage supply frequency then what happen to the voltage across a capacitor ?? I rekon the voltage gonna increases and the I going to decrease to negligible.
22. ### Finding capacitance

Homework Statement This is my data of Irms and angular frequency, and I have to plot the graph and teacher told me that the gradient will be capacitor's capacitance? Homework Equations The Attempt at a Solution Did do anything wrong?