A huge circular arc of length 4.4 ly subtends an angle '4s' at the centre of the circle. How long it would take for a body to complete 4 revolution if its speed is 8 AU per second?
Given : 1 ly = 9.46 $\times$ 1015 m
1 AU = 1.5 $\times$ 1011 m
Solution
$R = {l \over \theta }$<br><br>Time $$ = {{4 \times 2\pi R} \over v} = {{4 \times 2\pi } \over v}\left( {{l \over \theta }} \right)$$<br><br>put l = 4.4 $\times$ 9.46 $\times$ 10<sup>15</sup><br><br>v = 8 $\times$ 1.5 $\times$ 10<sup>11</sup><br><br>$\theta = {4 \over {3600}} \times {\pi \over {180}}$ rad.<br><br>we get time = 4.5 $\times$ 10<sup>10</sup> sec.
About this question
Subject: Physics · Chapter: Rotational Motion · Topic: Centre of Mass
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