One is due to force means direct force which would be the shear, shear stress will come into picture one another is will come due to eccentricity and the stress will come due moment.
एक है बल अर्थात प्रत्यक्ष बल के कारण जो shear होगा, shear stress देखने में आएगी और दूसरा आएगा उत्केन्द्रता के कारण और तनाव moment के कारण आएगा।