Which of the following is incorrect about Newton’s second law of motion?

Question

Question

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The second law of motion F = ma is applicable to a single point particle.
The second law of motion is a scalar law
The second law of motion is a local relation which means that force ‘F’ at a point in space at a certain instant of time is related to ‘a’ at that point at that instant.
In the second law, F = 0 implies a = 0

Answer 1

The correct answer is The second law of motion is a scalar law.

Key Points

Newton’s second law of motion is a vector law, not a scalar law, as it deals with quantities like force and acceleration, which have both magnitude and direction.
The mathematical expression of the second law is F = ma, where 'F' and 'a' are vectors, and 'm' is a scalar quantity representing mass.
This law is applicable to a single point particle, describing how a force acting on it results in acceleration in the direction of the force.
The second law is a local relation, meaning the force 'F' at a specific point in space and time is directly related to the acceleration 'a' at that point and time.
According to the second law, if the net external force (F) acting on a system is zero, the acceleration (a) of the system is also zero, implying the system is in equilibrium or moving at a constant velocity.

Additional Information

Newton's Second Law of Motion:
- It states that the rate of change of momentum of a body is directly proportional to the applied force and takes place in the direction of the force.
- The equation is written as F = ma, where F is the net force, m is the mass of the object, and a is the acceleration.
Vector Quantities:
- These are physical quantities that have both magnitude and direction, such as force, velocity, acceleration, and displacement.
- Newton's second law inherently involves vector quantities, as force and acceleration must be aligned.
Scalar Quantities:
- These are quantities that only have magnitude and no direction, such as mass, speed, energy, and temperature.
- Newton's second law is not scalar because it involves directional properties.
Applications of Newton's Second Law:
- It is widely used in engineering and physics to design vehicles, structures, and machinery by calculating forces and accelerations.
- It also explains everyday phenomena like why heavier objects are harder to accelerate compared to lighter ones.