Effects of a force acting on a body When a single resultant force acts on a body, which of the following outcomes may occur?

Introduction / Context:
Forces can do more than merely start or stop motion. In structures and machines, forces may alter velocity, balance other forces to produce equilibrium, and induce internal stresses that must be resisted by material strength. This question checks your holistic understanding of force effects.

Given Data / Assumptions:

• Body can be rigid or deformable.
• Other forces may already act; adding a new force affects the net resultant.
• Internal stresses arise when materials resist deformation.

Concept / Approach:
From Newton’s second law, a nonzero resultant force changes motion (acceleration). If an applied force is chosen to cancel the existing resultant, the new net force can become zero, creating static or dynamic equilibrium. Any external force transmitted through material sections generates internal forces and stresses that must satisfy equilibrium and compatibility.

Step-by-Step Solution:
Option (a): A nonzero net force changes velocity (magnitude and/or direction).Option (b): An appropriately directed force can balance others, making ΣF = 0.Option (c): External loading is resisted by internal stress resultants (tension, compression, shear, bending).Since all statements can be true, choose “all of these.”

Verification / Alternative check:
Consider a simply supported beam under a central load: supports apply forces that balance the load (equilibrium), yet internal bending stresses arise and if unbalanced, motion would change—illustrating all facets simultaneously.

Why Other Options Are Wrong:

• Selecting only one effect ignores other legitimate consequences of applying a force.

Common Pitfalls:

• Thinking “internal stresses” occur only in failure. They are always present whenever loads are carried.

Final Answer:
all of these