A wheel is subjectedto uniform angular acceleration about its axisInitially its angular velocity is zero In the first 2 sec it rotates through an angle a1 next 2 sec it rotates through an additional angle a2 the ratio of a2/a1

Dear pallavi

use the formula

Θ =ωt +1/2 α t²  

now first for 2 sec

a1 = 0 + 1/2 α *4

     =2α

now angel rotate in next 2 sec = angel rotate in 4 sec  - angel rotate in first 2 sec

                                   a2     = 1/2 *α* 16  - 2α

                                            = 6α

so a2/a1 = 3

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