Recent content by stupif

thank you very much...you help me a lot...appreciate your help...(bow)

but when i doing this in lab, my result from lab is quite big difference to the theoretical result. the aim of the lab is to determine the forces in members and the model is same as the diagram. the force applied is also same. What is the possible source of errors? Do we need to consider the...

Fbc = 0N?? is not tension and compression... then why this phenomenon happenned? i mean zero force members...

Fbc should be tension...i see it... my understanding about zero force members... zero force members are a member which cannot carry load. hence there is no force in these members. these members do not have compression force and tension force. the existence of zero force members are to...

thank you... Fbc = 20N?? Fbc = Fce cos 45 Fbc = 20N but why just now what i did is wrong? i feel like is correct because Fx = 0 Fx contain Cx, Fbc, Fce cos 45, that's why i formed a equation.Fab = tension Fae= tension Fbe = compression Fde= compression Fce= tension Fbc = compression

ok...i got it...thank you now these are my answer...could you help me check and are they correct? C joint (vertical) Cy - Fce sin45 = 0 20 - Fce sin 45= 0 Fce = 28.28N (horizontal) Cx + Fbc - Fce cos 45 = 0 -20 + Fbc - 28.28cos 45 = 0...

i don't understand about roller support there... how to know the force is in which direction? i thought the roller support 's force is always oppose to the force applied(20N)... thank you

[b]1. every member is 0.45m and all the angle is 45degree... C is fixed support, D is roller support [b]3. Ʃfx = 0 , Cx = 0 Ʃfy = 0 , Cy + Dy = 20N ƩMc = 0 , 20(0.45) + Dy(0.45) = 0 Dy = -20N...

[b]1. an 85kg jogger is heading due east at a speed of 3m/s. A 55kg jogger is heading 39degree north of east at a speed of 3m/s. Find the magnitude and direction of the sum of the momenta of the two joggers. [b]2.i have no idea about this question...can someone tells me what is this...

[b]1.A 0.16kg ball makes an perfectly elastic head on collision with a second ball initially at rest. the second ball moves off with half the original speed of the first ball [b]2. what fraction of the origianl kinetic energy gets transferred to the second ball? answer=108J i...

[b]1. A big fish with its mouth wide open is moving at 2.0m/s towards a school of small fish each of mass 300g. the small fish enter the wide mouth of the big one with a velocity of 5m/s to the opposite durection at the rate of 20fish per min. the big one is motionless after 13min : the big one...

what u mean? but i use Newton's law of restitution to get the answer. e=(v1-v2)/(u2-u1) -4.85=v1-v2---------second equation and i finally get the answer.

https://www.physicsforums.com/showthread.php?t=519410 can you help me this question?

i got it...thank you very much~

[b]1. a 7g bullet is fired into a 1.5kg ballistic pendulum. the bullet emerges from the block with a speed of 200m/s, and the block rises to a maximun height of 12cm. find the initial speed of the bullet and the kinetic energy lost of the bullet. answer: 528m/s, 835.7j [b]2. mu+ mu = mv + mv...