Look kartik the weight of body 100N is at an angle thetha ...for that we have resolved the components also. N2 is normal to the surface of bolck which is inclined...as already we have resolved the components for 100N ,no need to resolve the components for N2 ... because N2 and the components which we have resolved are in same co ordination system.. If you wanna resolve N2 you can do that but for that case , components of weight are not required Hope you will get this now.
FBD of b block is wrong. You didnt resolved N2
because it does not have to be resolved! the entire co ordinate system is relative here, its not wrong.
250/9.81 × a ????? Fbd of A
Look kartik the weight of body 100N is at an angle thetha ...for that we have resolved the components also.
N2 is normal to the surface of bolck which is inclined...as already we have resolved the components for 100N ,no need to resolve the components for N2 ... because N2 and the components which we have resolved are in same co ordination system..
If you wanna resolve N2 you can do that but for that case , components of weight are not required
Hope you will get this now.