EARTH SCIENCE
EARTHQUAKES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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when rocks are pulled apart
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when rocks fold or break
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a rock deep underground is pushed by weight above it, rock cannot move, it cannot deform
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parallel forces move in opposite directions
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Detailed explanation-1: -In summary, shearing stress is a type of stress that acts parallel to a cross-section of material. Shear forces cause this stress to occur. It is the force acting in the opposite direction and of the same magnitude on the opposite sides of the body.
Detailed explanation-2: -If the direction of the force is parallel to the plane of the object. The deformation will be along that plane. The stress experienced by the object here is shear stress or tangential stress. It arises when the force vector components which are parallel to the cross-sectional area of the material.
Detailed explanation-3: -Shear Stress. When a force acts perpendicular (or “normal") to the surface of an object, it exerts a normal stress. When a force acts parallel to the surface of an object, it exerts a shear stress. Let’s consider a light fixture hanging from the ceiling by a rope.
Detailed explanation-4: -This means that the actual shear stresses are opposite to the shear stresses in Figure 5.36c. In the cross-sectional plane therefore the actual shear stress acts downwards, which is entirely in line with the direction of the shear force.
Detailed explanation-5: -A shear stress is positive if it acts on a positive face in a positive direction or if it acts on a negative face in a negative direction.