Question

(Problems and
Problems
1. Two cylindrical shafts have the same length and mass are made of the same material.
One solid, while the other which is hollow has an external radius twice the internal
radius. Compare their torsional rigidities,
​

Answer 1

Answer:

Give, Both shafts have equal size, means outer diameter of the shaft is same,

Hallow shaft

Inner diameter =d

i

Outer diameter =d

0

Ref. image 1

Solid shaft

Outer diameter =d

0

Ref. image 2

→ If the size is same, There is more material used in the solid shaft, hence solid shaft will be stronger,

Assertion - wrong

→ Torsional rigidity of solid shaft is more than the torsional rigidity of the hollow shaft

Hence more torque is required in the solid shaft to produce the same deformation.

Reason - wrong