Recent content by jeeloong

Thanks boneh3ad, I completely agree with you the sudden spike in acceleration at the end of experiment is due to test apparatus breaking surface. However, the one with small streamlined swim cap with sudden rise in acceleration at 0.6 s is really puzzling. I believed it has something to do with...

You are right boneh3ad, the Cd for goggle is out of context given that Cd of 0.8!

I am letting the object float to the top using buoyant force. Sorry there is some error in my calc the C_d for swim cap with goggle is 0.5++ as I forgeet to include v to the square. The surface under the cap is normal polystyrene foam with some grain boudnaries as u can see. THe swim cap is...

By the way terminal velocity is only obtained for body with goggle and body with large cap. as u can see the acceleration is approaches zero.

The sudden rise in acceleration at 1.2s is due to the fact that the body has escape out of water surface! and moving into less dense medium that why suddenly accelerate again until being overcome by gravity and decelerate downward!

Dear Experts, I am 4th year undergraduate who did experiments for drag reduction in swim cap. I had applied hydrophobic and hydrophilic coatings on my cap. My final results are shown in attachment below. The no cap has more drag than body with swim cap without coatings. There is not much...

Dear Experts! I currently have a sets of data with different time interval and I plotted it into MATLAB from excel. Is there a way for me export the files or calculate the mean, standard deviation etc so that I can calculate error etc. It would be great if I could do it in Matlab. I am...

Dear Experts! I am currently try to measure the drag of an buoyant object. I did 10 replicates, in general terms 10 tests all with the same set-up and same release mechanisms. To start off with I will explain my project: Drag reduction in swim cap First of all I got one accelerometer...

Yeah, I need to reach terminal velocity as quickly as possible. My supervisor mention getting terminal velocity correctly is a challenge. my water tank is about 3m depth.

Hello I got the follow result 1) Bottle with accelerometer and off center of mass 2) Bottle with acc with aligned center of mass I already attach the image in Simon posts, can't duplicate. Thx!

Hi, Thanks for the reply I got this data doing the test using a bottle with accelerometer fitted. The first one is without mass inside just accelerometer. The center of mass is not aligned with the bottle and it shot up very fast(haven't reach constant velocity/terminal I guess). The second...

Dear Experts, I really need help with the calculation of virtual mass and drag of an object. Firstly, I am doing final year project called Drag reduction in swim cap. Before I go into using swim cap. I am try to measure the drag using accelerometer that inside a bottle but I am damn...