Question

A wheel starting from rest is rotating with a constant angular acceleration of 3rad/s².An observer notes that it traces an angle of 120 radians in 4sec interval. For how long the wheel has been rotated when the the observer started his observation?


DON'T POST UNNECESSARY ANSWERS

IF ANY ONE GAVE CORRECT ANSWER I WILL MARK AS BRAINLIEST

PLEASE

#ANSWER QUICK#​

Answer 1

Angular acceleration α=3rad/s  

2

 

From rotational kinematics:

θ=ω  

1

​  

t+  

2

1

​  

αt  

2

 [during the 4s internal]

60=4ω  

1

​  

+  

2

1

​  

×3×16

=4w  

1

​  

+24

4ω  

1

​  

=36

ω  

1

​  

=9rad/s

The wheel starts from res, therefore ω  

0

​  

=0

ω  

1

​  

=ω  

0

​  

+αt  

′

 

 

9=0+3t  

′

 

 

t  

′

 

=  

3

9

​  

=3s

Answer 2

Explanation:

please ask your questions