Given below are two statements :
Statement (I) : The limiting force of static friction depends on the area of contact and independent of materials.
Statement (II) : The limiting force of kinetic friction is independent of the area of contact and depends on materials.
In the light of the above statements, choose the most appropriate answer from the options given below :
Statement (I) : The limiting force of static friction depends on the area of contact and independent of materials.
Statement (II) : The limiting force of kinetic friction is independent of the area of contact and depends on materials.
In the light of the above statements, choose the most appropriate answer from the options given below :
- Statement I is correct but Statement II is incorrect
- Statement I is incorrect but Statement II is correct
- Both Statement I and Statement II are incorrect
- Both Statement I and Statement II are correct
The Correct Option is B
Approach Solution - 1
To determine the correct answer, we need to evaluate the accuracy of both statements regarding the nature of friction:
- Understanding Static Friction:
- Static friction is the frictional force that prevents two surfaces from sliding past each other.
- The limiting force of static friction depends on the nature of the surfaces in contact and the normal force, but it is independent of the area of contact.
- Therefore, Statement I is incorrect because it incorrectly states that the limiting force of static friction depends on the area of contact.
- Understanding Kinetic Friction:
- Kinetic friction is the frictional force that acts between surfaces in relative motion.
- The limiting force of kinetic friction is also independent of the area of contact, but it depends on the materials of the surfaces in contact.
- Therefore, Statement II is correct, as it correctly states that the limiting force of kinetic friction is independent of the area of contact and depends on materials.
Conclusion: Based on the analysis above, the correct answer is: Statement I is incorrect but Statement II is correct.
Approach Solution -2
The limiting force of static friction depends on the normal force and the materials in contact, but it does not depend on the area of contact. On the other hand, the limiting force of kinetic friction also depends on the nature of the materials in contact and is independent of the area of contact. Therefore, Statement I is incorrect, while Statement II is correct.
The correct option is (B) : Statement I is incorrect but Statement II is correct
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Concepts Used:
Friction
Friction is defined as the resistance offered by the surfaces that are in contact when they move past each other.
Types of Friction
There are four categories of Friction- static friction, sliding friction, rolling friction, and fluid friction.
Sliding Friction
In Sliding Friction, the weight of the sliding object calculates the amount of sliding friction present between the two objects. The sliding friction is supposed to be greater as the pressure exerted by the heavy object on the surface it slides over is comparably more.
Rolling Friction
Friction between a circular object and the surface is called as Rolling Friction. It is required to overcome sliding friction is more than the force required to overcome the rolling friction.
Static Friction
Friction that keeps an object at rest without initiating any relative motion between the body and the surface is termed as Static Friction. For example, a parked car resting on the hill, a hanging towel on the rack. The maximum force of static friction is directly proportional to the normal force.
Fluid Friction
Fluid Friction is the kind of friction that is exerted by the fluid on the object that is moving through a fluid.