### 30. Advance Illustration | Rigid Body Dynamics | A Rod supported by Strings | by Ashish Arora

in this illustration we’ll analyze, the situation

of a rod supported by strings. here the figure shows a rod ay b length of l and mass m supported

by 2 strings which are of equal length and in extensible. and here we are required to

find tension in 1 string just after other string is cut. so, in, situation we can analyze

when 1 string is cut the situation would be like this, say, this is the rod. and this

is only in the support of. the string at end b and string at end ay is say snapped, so

due to this what happens. the weight of rod will cause, a rotational motion in rod, and

a tension in the other string which remaining is say t. then we can write. if acceleration

of, center of mass, of rod, just after. 1 string is cut. is ay, and, angular acceleration.

is alpha. then here we use, we can write 1 equation as, m g minus t is equal to m ay.

because center of mass is coming downward acceleration ay, and if it is rotating at

an angular acceleration alpha about end b. then, the torque of tension about b is zero

only due to the torque of m g it will rotate. so we can write m g multiplied by. l by 2.

is equal t, i alpha which is m l square by 3. multiplied by its angular acceleration

will be, ay upon, l by 2 in this case because, the acceleration of center of mass we can

write as l by 2 alpha. so, if this is our equation 1 and this is equation 2. we can

simplify that equations and here we can get, from. equation 2. here the value we are getting

for, ay is, 3 gee by, 4. now, from equation 1. we can write m g minus t is equal to m

multiplied by 3 gee by 4. and simplifying this is giving us the value of t. that is

m g minus 3 em g by, 4 that is equal to, m g by, 4 that is a result this problem.

## 3 thoughts on “30. Advance Illustration | Rigid Body Dynamics | A Rod supported by Strings | by Ashish Arora”

Sir,how can we take point of junction of string and rod as point of IAOR? How is it possible? Rod is more likely to rotate about point of suspension..

Sir ,what will be initial point of rotation if a spring is used instead of string

Sir wen is booster classes for dynamics starting coz it is not showing any schedule