Newton’s second law – relation among force, mass, and acceleration Newton’s second law of motion ________ a relation between the applied force and the mass and acceleration of a moving body.
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Agives
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Bdoes not give
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Cgives only for constant velocity
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Dgives only for zero mass
Answer
Correct Answer: gives
Explanation
Introduction / Context:Newton’s second law formalizes dynamics by connecting cause (net force) and effect (acceleration) with the property of inertia (mass). It is foundational in engineering mechanics and physics.
Given Data / Assumptions:
- The net external force F acts on a body of mass m.
- Acceleration a is the time rate of change of velocity of the body.
- Classical mechanics regime (non-relativistic speeds).
Concept / Approach:The law states: F_net = m * a (vector form). It directly relates the magnitude and direction of the net force to the mass and acceleration of the body. For varying mass systems, a generalized form uses momentum: F_net = d(mv)/dt.
Step-by-Step Solution:
Start from momentum p = m v.Newton’s second law: F_net = dp/dt. For constant mass, dp/dt = m dv/dt = m a.Thus, the acceleration produced is proportional to the net applied force and inversely proportional to the mass.Verification / Alternative check:Dimensional consistency: [F] = kg·m/s^2, [m a] = kg·m/s^2. Experimental validation spans from particle dynamics to rigid-body motion.
Why Other Options Are Wrong:
- ‘‘does not give’’ contradicts the statement of the second law.
- ‘‘only for constant velocity’’ would imply zero acceleration and thus zero net force, which is a special case of no net force, not the general law.
- ‘‘only for zero mass’’ is nonsensical; the law is meaningful for finite mass.
Common Pitfalls:Confusing net force with a single applied force while ignoring opposing forces, or forgetting vector directions in multi-force systems.
Final Answer:gives