00:01
Let us first draw the fbd.
00:04
This is the section and this is the so at this point we end we have a torque of 600 newton meter and at this point we have a torque of 350 newton meter 350 lb fit it's not a newton meter it's in lb fit is in lb fit and at point a let the torque is t a this point a so let's write the moment equation so net moment will be 0.
00:47
So we will get minus t a plus 600 minus 3 minus 350 is equals to 0 but from here we get t a is equals to 250 i'll be fit now now let's consider let's further similarly we can find out the net torque at point b so we will write summation of m is equal to 0.
01:20
So let's put 600 minus 350 minus 450 plus t b is equal to 0 so from here we get t b is equal to t b is equal to 200 lb fit let's now calculate the polar moment of inertia of this act so it will be j they will be equals to 5 divided by 2 5 divided by 2, ro to the power of 4 minus r to the power of 4.
01:59
R is the radius.
02:01
O denotes the outer radius, i denotes the inner radius.
02:03
So let's put the values 5 divided by 2.
02:06
Value of ro is 2 .5 divided by 2 to the power of 4 minus the ri is 2 .3 divided by 2 to the power of 4 packet closed.
02:28
So from here we get the polar moment of inertia is equal to 1 .08 inch to the power of 4.
02:40
Now let's calculate the c .r stress at point a.
02:44
So let's calculate c .r.
02:45
Stress point a at point a at point a.
02:52
C .a stress at point a will be equal to torque at point a multiplied by radius divided by the polar moment of inertia.
03:01
So let us put the values here.
03:03
Torque we have calculated 250 multi multi 250 l b fit so let us convert it into inch fit so it will be 250 lb fit multiplied by 12 inch divided by fit multiplied by radius is 2 .50 divided by 2 inch divided by 2 inch divided by the polar moment of inertia we have calculated 1 .08 inch to the power of 4 so from here we get here stress at point a is equal to p .46 .69 psi or it will be equals to 3 .45 psi.
03:59
So this is the required crstase at point a.
04:04
This is 0 .3 .3 .45.
04:08
Similarly at point b at point b we can calculate here stress at point b is equal to torque at b multiplied by radius, ro radius, outer radius divided by the polar amount of inertia.
04:30
The torque at point b is 200 lv perfit...