AP EAPCET 25-Aug-2021 Shift 1 Paper

Let, the speed of bus be vB and that of cyclist be vC.
Case 1 Bus moving from A to B,
Relative speed of bus =vB−vC=vB−20
Distance covered = Velocity × Time
d=(vB−20)×18 ...(i)
Case 2 Bus moving from B to A,
Relative speed of bus =vB+vC
=vB+20
Distance covered = Velocity × Time
d=(vB+20)×6 ...(ii)
From Eqs. (i) and (ii), we get
(vB−20)×18=(vB+20)×6
⇒vB=40‌km∕h
From Eq. (ii),(vB+20)×6=vBT
⇒(40+20)×6=40×T
⇒T=9 min =

9

60

h=

3

20

h.