(0) The extra time the time latest blue bal to reach ts maximum height an return tte
lunch point. takes 030-108 >t 3.05 to gett the topo T= 6s
o
(} Let rbe the time at which decaeration tarts and Tthe required time for the entire motion. The
deceleration LA 80, hence 7=£=30. The 108
Area oTer=90. Hence,
(i straight Ine untl? followed by concave down parabola wth zero slope at + 64
y=0+30:8-x10:80' =-80m. Teele 20m
m 20-10:802-50ms
(U) The height above the te 0-30 O 45m. The distance traveled
15 45145180 170m so the average sped ls
(e) Lette na veocky be u. Then at ¢=2 the velocity =u~10%20 andat¢= 4
ve =U=10%40. Me have that y, =, £0 u-10x20--W-10x40) or 20-60 £0 430m
aivelociy component is y, 20-10x20=-20m5", The angle with the horizontals
y=012+254n19 204654 1108204654" -285m. Bottom of bulls at het of
285-0.12- 273 ma0 the ball goes over the crossbar. Something ike Roberto Bags
(At the lowest pont the resultant forces T=mg and so T-mg = e Ris the length of
the string By energy conservation: maß = Em => mv! =2mgR, Henc
ofresoutionsis 398240
Dan
= srods
207 LE 9373.032m
707 750
16) From M atx yla la . SHE rhen the required ratios
(62 Atthe top point onthe rack the resultant forces Ns mg and N
20H =4GR eV >! =2gH SR. Hence ph = 29-49 =H,
Tsind amg and Teo Le the reutant fo
tensions the hypotenuse of a igh onged tran
ET
(the angles found from: 0-15)
rc proportonalto speed Stokes wil ae on the body epposng the motion
force wi neeace scent otra the ne fore on te body
v 205010), 5.9, 2300-1100
6416
1 There when the largest and amas possible mare a
Ke energy before the o
Lao,
“The acelration increases because the force the same but the mass decreaces
‘The sceieration becomes zero when al the felis used up.
(One panic welcty makes an ange with the orgnalincident partie direction. The othe
Apalyng conserition af mementum song the erection ofthe incident pace and
angerto we fe:
ne
ova sone
Omen mn Arte
Bernd weed
We have two equations fortwo unknowns:
u=ves6+winé
O-vaind-wens®
From the second: wavtand. Subaitingin the fe
Uaveossevtandilnd end) Hence, v=ucosó.
Then, wavtand =ucorStand using
Tenia Kinetic energy Lut. The Sialic
Much +
Se, the clon east
(Forthoze we know vectors, there ira much simpler olution: et be the inital
momentum, and À, À, the moments ofthe two particles after the coliion. Then
‘Thus, aking dot product:
PPB +B BAIA AA
Pp + pl Since BO because the vectors are perpendicular
Tu 2 and kinetic energy is conserve)
Practice exam-style questions
A.1 Kinematics.
Papert
Paper 2
1=022: (or show calculation i fl)
Straight line up rom 2er to r= 0.
with gradient of
Time to reach net
Distance fallen = 0.064 m
0064 < (024-015) m
Usev=u rat
Truck has constant sped (horizontal line) of 15 a +
Car stare at origin and ives a a tsiht line to 24m 0 at 10
Froa 10 à t 15 scars speed is shown by a horizontal Kine
Afr 625 +
‘After 10 the caris 30 behind the tl
‘Another 3.3 «before they have travelled the came distance,
Tota time