A disc initially at rest, is rotated about its axis with uniform angular acceleration. In the first 2 s, it rotates an angle θ . In the next 2 s , the disc rotates through an angle

Question

A disc initially at rest, is rotated about its axis with uniform angular acceleration. In the first 2 s, it rotates an angle θ . In the next 2 s , the disc rotates through an angle (A) θ  (B) 2θ  (C) 3θ  (D) 4θ

Tardigrade Admin · Accepted Answer

Because of uniform angular acceleration. we can use the equation of motion in rotation θ =(1/2) α (2)2 [ω0=0] θ =2α And θ +θ '=(1/2)α (2 + 2)2 [∵ ω0=0] θ +θ '=8α Hence, θ '=3θ

Q. A disc initially at rest, is rotated about its axis with uniform angular acceleration. In the first $2 s,$ it rotates an angle $θ$ . In the next $2 s$ , the disc rotates through an angle

$θ$

$2 θ$

$3 θ$

$4 θ$

Because of uniform angular acceleration. we can use the equation of motion in rotation
$θ = \frac{1}{2} α (2)^{2}$ $[ω_{0} = 0]$
$θ = 2 α$
And
$θ + θ^{'} = \frac{1}{2} α (2 + 2)^{2}$ $[∵ ω_{0} = 0]$
$θ + θ^{'} = 8 α$
Hence, $θ^{'} = 3 θ$

Q. A disc initially at rest, is rotated about its axis with uniform angular acceleration. In the first 2s, it rotates an angle θ . In the next 2s , the disc rotates through an angle

θ

2θ

3θ

4θ

Because of uniform angular acceleration. we can use the equation of motion in rotation θ=21​α(2)2[ω0​=0] θ=2α And θ+θ′=21​α(2+2)2[∵ω0​=0] θ+θ′=8α Hence, θ′=3θ

Q. A disc initially at rest, is rotated about its axis with uniform angular acceleration. In the first $2 s,$ it rotates an angle $θ$ . In the next $2 s$ , the disc rotates through an angle

$θ$

$2 θ$

$3 θ$

$4 θ$

Because of uniform angular acceleration. we can use the equation of motion in rotation
$θ = \frac{1}{2} α (2)^{2}$ $[ω_{0} = 0]$
$θ = 2 α$
And
$θ + θ^{'} = \frac{1}{2} α (2 + 2)^{2}$ $[∵ ω_{0} = 0]$
$θ + θ^{'} = 8 α$
Hence, $θ^{'} = 3 θ$