Question

64. What will be the time 5 hours after 9:30 a.m.? Choose the correct answer from
the following:
(a) 15:30 a.m.
(b) 15:30 p.m.
(c) 2:30 p.m.
(d) 2:30 a.m.​

Answer 1

Answer:

Answer:

Angular retardation of flywheel = π/10  rad/s²

Explanation:

Given:-

Initial angular velocity of flywheel = 360 rpm

Final angular velocity of flywheel = 180 rpm

Time taken for change in angular velocity = 1 min = 60 sec

To find:-

Angular acceleration (retardation) of the flywheel, a =?

Formula required:-

Formula for angular acceleration

        a = Δω / Δt

[ where a is angular acceleration, Δω is change in angular velocity, Δt is change in time ]

Solution:-

Converting the angular velocities given in rpm into rad/sec

→ ω₁ = 360 rpm = 360 × 2π/60  rad/sec = 12π rad/sec

→ ω₂ = 180 rpm = 180 × 2π/60  rad/sec = 6π rad/sec

Calculating the angular acceleration

→ a = Δω / Δt

→ a = (12π - 6π) / (60)

→ a = -6π / 60

→ a = -π/10  rad/s²

Therefore,

Angular retardation of the flywheel is π/10  rad/s².

Answer 2

Step-by-step explanation:

. What will be the time 5 hours after 9:30 a.m.? Choose the correct answer from

the following:

2:30 p.m