Question

HCF(P,12)=6 LCM(P,12)=36

Answer 1

Given speed of the vehicle=72㎞/hr
=72×
18
5
​
=20m/s
radius of the wheel =
2
0.5
​
=0.25
initial angular velocity (ω
0
​
)=
0.25
20
​
=80rad/s
angle covered after applying brakes=20×2π=40π
let the angular retardation be −αrad/s
2

final angular momentum ω=0
putting formula ω
2
=ω
0
​

2
−2αθ
⇒0=ω
0
​

2
−2×α×θ
⇒ω
0
​

2
=2×α×θ
⇒80
2
=2×α×40×π
⇒α=
80×π
80
2

​

⇒α=
π
80
​

putting the value of π=3.14
α=25.47rad/s
2

so retardation is −25.477≅−25.5 rad/s
2
Lcm hcf 36+3666