- Messages
- 140
- Reaction score
- 61
- Points
- 38
since work done here is the work done against gravity+ gain in potential energy + gain or loss in kinetic energyhttp://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s12_qp_42.pdf
Please I need help with #6 (ii) and #7 , how do i draw the graph? If anyone could draw it it would really be helpful if you post a picture of the graph Thanks!
to calculate gain or loss of kinetic energy we need final and initial velocity
now we are available with initial velocity = 6 ms^-1 =V1
power at bottom of the hill=P1
Force at the bottom of the hill =F1
now at top f the hill velcity =?
Power=P2=5*P1
Force=F2=3*F1
recall the formula P=Fv
take the ratio of both
(
now we have
(5*6/3)=10=V2
now
work done against gravity+ gain in potential energy =945000
kinetic energy change = 0.5*1250*(10^2-6^2)=625*64=40000
therefore
945000+40000=985000=work done