Recent content by depre87

Homework Statement http://imageshack.us/photo/my-images/855/10544781.png/ Homework Equations a=[r''-r0'^2]er+[r0'' + 2r'0']e0 where 0 = theta The Attempt at a Solution stumped about it, I've tried setting the above to 0 then work out r which is 200 m but that's just cluelessly...

Homework Statement y'=(1-y)(3-y)(5-t) Homework Equations find equilibrium solutions of ODE and determine their stability The Attempt at a Solution equilibrium solutions are y = 1 and y = 3, I'm not sure how to determine their stability without some form of a slope field, is it...

oh wow I am so silly... thankyou so much!

Homework Statement Mobile phone is dropped onto a hard floor from a height of 1.5m. The mass of the mobile phone is 0.2 kg. After the impact, the phone bounces to a maximum height of 50 mm. The phone is estimated to be in contact with the floor for 0.005s. Which is of the following is the...

Homework Statement Force exerted on a car by a crash barrier as the barrier crushes is F=-(4.5+140s) kN where s is the distance in metres from the initial contact. If a car of mass 2000 kg is traveling at 100 km/h when it hits the barrier the barrier deformation required to bring the car to...

Homework Statement http://answers.yahoo.com/question/index?qid=20090812013110AAcrnFs Homework Equations Equilibrium - Fx = Fcos(theta), Fy = Fsin(theta) The Attempt at a Solution I've got the answer however it's different to the one posted the link above - isolated the top pipe...

I just had a look and I don't understand it enough to apply it to my question, could you enlighten me? thanks for the suggestion though.

Homework Statement Show if V is a vector space ([a,b,c]|ab>=0). I'm trying to test whether it is closed under vector addition. Homework Equations v=[a1,b1,c1] w=[a2,b2,c2], v and w satisfy ab>=0 a1b1>=0, a2b2>=0 show (a1+a2)(b1+b2)>=0 The Attempt at a Solution Got to a1b1...