Question

A heavy uniform rod of mass 7 kg and length 5 metres is suspended from a from point by inextensible strings fastened to its ends , their lengths beings 3 and 4 m . Find the tensions in the string.​

Answer 1

Answer:

Step-by-step explanation:

ension in the string before snapping,

2T=mg

Torque on the rod,

T=  

2

mgl

​  

 

⇒Iα=  

2

mgl

​  

 

⇒  

3

1

​  

ml  

2

α=  

2

mgl

​  

 

⇒α=  

2l

3g

​  

 

acceleration with which the centre of mass falls down,

a=  

2

lα

​  

 

=  

4

3g

​  

 

∴ma=F  

D

​  

−F  

U

​  

 

⇒m  

4

3g

​  

=mg−T  

′

 

⇒T  

′

=mg−  

4

3mg

​  

 

⇒T  

′

=  

4

mg

​