00:01
Element is like this this is ab this is ac all right and this is b b c a b and c this is 1 .2 meters this is 1 .5 meter all right this is given to us now it says that ab can support a maximum of 2 kilo newton this has t max value of 2 kiloons this has t max value of 0 .8 kilo newton this has t max value of 0 .8 kilo newton we need to calculate that how much force f should be applied in this vertical direction.
00:43
All right.
00:43
So over here in this question, we will try to find these angles.
00:49
So how do we do that? now we could clearly see that if we know these two angles, let us say this is theta and this is five.
01:04
If we know we know these two angles, then we would calculate these two angles as well.
01:08
Let this would be 90 minus 5 this would be 90 minus theta and if you now rate the tension into two components this is tac let us say this was tab then this would be five and this would be theta so tac cos f f is equal to tab course theta this is known to us all right and this f force if we try to balance the force in the vertical direction then f would be equal to t a c sine 5 plus t b a b sine theta this will be the value of the force right so we will see that from here we will see that which one is limiting which one is limiting all right and from here we will calculate all right for checking this that which one is limiting we need to calculate the value of these theta's all right so the value of theta we will calculate using the principles of triangle.
02:24
So this was 1 meter.
02:29
This is 1 .2 meter.
02:32
This was 1 .5 meter.
02:35
So let us say this is x.
02:37
This would be 1 .5 minus x.
02:40
This was theta.
02:42
This was 5.
02:44
This is a.
02:45
This is b.
02:46
This is c and let us say this is d.
02:49
All right.
02:50
So now what we will do is in the.
02:55
This left triangle this cos theta is x over 1 all right and cos phi is 1 .5 minus x over 1 .2 all right so also using the cosine law we can write for this whole triangle cos 5 would be equal to this 1 .5 square plus 1 .2 square minus 1 square divided by 2 into 1 .5 into 1 .2 square.
03:43
Alright? so we'll put this value over here.
03:46
Let me calculate the value 1 .5 plus 1 .2 square minus 1 divided by 2 into 1 .5 into 1 .2...