Recent content by tommy060289

Homework Statement Dear physics forum users, I have a bit of a question about using a propellor to provide resistance. I am looking at designs for fall arrest devices and one idea I've looked at is using a propellor connected to a reel so that when the reel is unwound the propellor spins and...

No worries, figured I can get it to change by adding: *(Pi()/180) on the end

Dear all, I am currently using excel to work out some values for incident solar radiation but I am running into a rather frustrating problem when I try to do the following: =COS(9.863) my calculator tells me correctly this is 0.985. however, when I put this in excel it decides it...

thanks peter, ill try that!

But I'm still struggling going about calculating the distance in which the object is stopped. Is there anyway to calculate this. I could use young's modulus but again, the problem lies in calculating the stress?

Hey everyone Homework Statement Im trying to calculate the force encountered by an object falling due to gravity that is caught by a rope. Obviously F=ma and since mass is constant I need to find the rate of deceleration. I've tried to using the equation v^2 = u^2 +2ax as v = 0 and u...

Hey everyone, I have a slight question regarding the current draw from an inverter If you had a 100W pump running on 230V obviously it's current draw is 100/230 which is 0.43 Amps but what if you were running the water pump from an inverter connected to a 12V battery. Would the current...

Homework Statement Hey everyone, as part of a final year project I am looking at the economic feasibility of solar panels and whilst I have solar data for radiation intensity on flat surface, longitude (and plus or minus 15°) and 90° I am trying to find a calculation of intensity at any...

33m is the required spec for the project we've been given at university. I havnt posted it in the coursework section as I thought it would be better to post here about generating ideas than answering a specific question. I have looked at the designs around atm and one that caught my eye was...

Hey Everyone, I'm currently looking at designing a device that would allow people to escape from working at heights quickly and safely in the event of an emergency (up to 33 m) I know there are some products on the market already but since I don't have a great deal of experience with them...

so are you saying I should use V = IR to calculate voltage drop or current loss? surely it wouldn't work for voltage drop as when current is dropped and voltage is increased, the voltage drop reduces. Im not entirely sure what to do with my current losses though as here is the set up. I have...

Hey everyone, I could do with a hand checking my understanding of calculating the current loss in cables just to make sure I am doing it right. First up, is power loss. From my understanding of ohms law and P=VI it is possible to calculate the power loss in cables by using the formula power...

thank you so much nvn, I don't think I could have done this without all your help! It is very much appreciated! Now all I have to do is find a book with the table in for pipe bends so I can reference it and I'm finished with my pump calculations! Once again a very big thank you!

My apologies nvn, i adjusted the design before i did the arrangement drawing and as such the flow rate Q became 0.0009831 m^3/s. i thought I had posted that but I must have forgot. Everything else is correct so I expect that adjustment shoudl account for the majority of the difference. The...

Hey nvn, I don't really understand the formula you have you used the calculate the equivalent pipe length. as 0.25/0.019 is 1316, where has the 16.1*d come from? Also, for my pipe length, I worked out where the straight pipe section intersects the curve (as it doesn't go a full 90 degrees)...