# Search results

1. ### Need help identifying cog

Xxx Xxx xxx xxx
2. ### Differential Question

Hi. I have a quick question about a differential made up of 4 bevel gears. Say there are two axles which go into either side of the differential as shown in the diagram. Both axles have a pin mounted at the end to track its position radially, initially both pins point up...
3. ### Translating Motion - Which is the most efficient?

Hi. I need some wisdom! Here is my problem. I want to make an air powered engine. This isnt a problem, I have plans for this. However, I want to put my own twist on the engine. I want it to be a axial engine, so the axle is in the same plane as the cylinders. The importance factor is...
4. ### What mechanism is this?

Hi, I was just wondering what kind of mechanism is used in this video It converts the up and down movement into rotational movement, and it all seems very compact and smooth. James

Hi, I have a question about one of the engines im looking at for a project. I am linking two cylinders together. One is a cylinder with a pivoting shaft (piston A), the other piston has a cylinder with a fixed axle so it can only move in and out (piston B). To allow piston be to move with the...
6. ### Working out Cam dimensions

Hi, Im trying to work out the dimensions of the offset on a cam for a project. I know the travel of rod c, as well as the length of the connecting rod b, but im not sure what the lenth of dimension a should be. I know this is probably simple maths (just pythagoras?) but I need to make sure I...
7. ### Simple Question about engine timing

Im looking at designs for a engine, but im giving myself a headache over something which is probably incredibly obvious. Ill explain it as simply as I can in text and ive drawn a (terrible) paint image to help explain it a bit better. There are two cylinders. One cylinder needs to have its...
8. ### Light defration - How can I distribute the light evenly

Hi, Im making a light at home, but I have a problem with it. The luxeon star being used to supply the light creates a large bright spot on the top lens, and leaves the rest of the lens mcuh darker. I now need to make a lens to sit over the luxeon star which will defract the light so it lights...
9. ### Revive Resistance - Series & Parrallel

Homework Statement Two resistors, when conected in series have a total resistance of 12.9KOhms, and when connected in parallel a combined resistance of 2.988KOhms. Derive the value of the individual resistors. Homework Equations R = R1+R2 ---Series 1/R = 1/R1 + 1/R2 The Attempt at...
10. ### Electrical Safety - Shocks - Model Answer?

Homework Statement a) You have been asked to design a convector heater (electric radiator) which has a metal body. Detail an appropriate method of preventing electric shock for users of this product, and show how such a protection strategy could be implemented in your design. (15) b)...
11. ### Mech - Girder Section - Picture included

Homework Statement http://img132.imageshack.us/img132/8958/mechanicsgv3.jpg [Broken] The Attempt at a Solution (i) Is the weight balanced on both sides in a situation like this, in which case it would be: Or are the weights not equal and infact im meant to work it out with...
12. ### Mech Help - Moment & Friction

Homework Statement http://img237.imageshack.us/img237/7580/mechhelpui7.jpg [Broken] 2. The attempt at a solution (i) Moment of F = 70 x 800 = 56000 Moment of weight = 500 x 270 = 135000 Therefore the trolley remains at rest. Is this right? (ii) Can you help me...
13. ### Dynamics - Another collision question

Homework Statement http://img291.imageshack.us/img291/7829/collisionok5.jpg [Broken] Homework Equations Conservation of momentum Conservation of Kinetic Energy GPE KE The Attempt at a Solution Ive done the first part of the question. With the second part, i thought about it...
14. ### Dynamics - Collision Question

Homework Statement http://img138.imageshack.us/img138/9476/phyus3mu7.jpg [Broken][/URL] Homework Equations Conservation of momentum Conservation of kinetic energy The Attempt at a Solution I really have no idea. I dont know the velocity of A before the collision and i dont know...
15. ### Dynamics - Velocity Question

Homework Statement http://img521.imageshack.us/img521/4360/physicsjg1.jpg [Broken] Homework Equations Elastic Energy = 0.5 x k x X² Kinetic Energy = 0.5 x m x V² The Attempt at a Solution At 1m i worked out there is 1.922J of energy (0.5 x 10 x 0.62²) stored in the spring. Since...
16. ### Projectile Problem - Angle

Homework Statement A projectile is fired at an angle of 30 degrees above the horinzontal with a velocity V0 of 460 m/s. Determine the radius of the curvature of the trajectory at the position of the particle 10 seconds after firing. Homework Equations V = U + AT The Attempt at a...
17. ### Parrelle Axis Theorem Help

Im having a hard time getting my head around this, any help would be much appreciated. Homework Statement Determine the position of the centroid and calculate the second moment of area about a horizontal axis passing through the centroid for the following sections shown. Attached is the...
18. ### Simple Dynamics Question

Homework Statement A projectile is fired at an angle of 30 degrees above the horizontal with a velocity V0 of 460 m/s. Determine the radius of the curvature of the trajectory at the position of the particle 10 seconds after firing. Homework Equations v = u + at s = ut +...
19. ### Mechanics & Statics book - Need Suggestions

Hey guys, Im doing mechanics and statics at a university grade level as part of my product design course (currently in year one). Can anyone recommend a good book as the one that i saw not only had tiny font that i couldnt read easily, but also was written in such a way as to send you...
20. ### Really basic resistance question, but not sure.

Hey guys, I feel like an idiot asking this, but if the question is talking about 1k7 ohms of resistance, am i to believe that is the same as 1700 ohms? Thanks ^^ James
21. ### Recommend a Mechanics book?

Homework Statement Im having a hard time in my mechanics class at my course. The teacher has recommended "Applied Mechanics" but the book looks incredibly dull and old fashioned. Im looking to buy another mechanics book. Im doing product design and at the moment we are learning about...
22. ### Dynamics Question - Simple but stuck

Homework Statement http://img511.imageshack.us/img511/3732/dynamics01fm7.jpg [Broken] Homework Equations F = M x A F = u (coefficient of friction) x N The Attempt at a Solution http://img508.imageshack.us/img508/7526/dynamics02ry1.jpg [Broken] W sin 30 = 50000 W cos 30 =...
23. ### Basic Circuit Diagram - Im stuck

This isnt a hard question im sure, but im new to circuit diagrams and need them as part of my product design course, so any help would be much appreciated. Homework Statement Find the currents which are flowing in the 14Ohm and 10Ohm resistor...