AP EAPCET 19-Aug-2021 Shift 2 Paper

Given, radius of wall, R=8m
Minimum speed, v=5√5ms−1
Acceleration due to gravity, g=10ms−2
Let coefficient of friction be µ.
According to diagram,f = mg ...(i)
∵ f = µN ...(ii)
where, f is friction force
and N is normal reaction = centripetal force
⇒N=

mv2

R

Substituting in Eq. (ii), we get
f=µ

mv2

R

...(iii)
Now, on equating Eqs. (i) and (iii), we get
f=mg=µ

mv2

R

⇒µ=

Rg

v2

=

8×10

(5√5)2

=

80

125

=0.64