📚 Learning Guide
Friction Forces Analysis (Part 3)
medium

If an object begins to slide down a surface at a weight of 270 grams, what could be the underlying reason for this change in motion in terms of friction forces?

Master this concept with our detailed explanation and step-by-step learning approach

Learning Path
Learning Path

Question & Answer
1
Understand Question
2
Review Options
3
Learn Explanation
4
Explore Topic

Choose the Best Answer

A

The static friction force has been exceeded by the gravitational force.

B

The kinetic friction force is stronger than the static friction force.

C

The weight of the object has decreased below the threshold for static friction.

D

The surface has become smoother, reducing friction.

Understanding the Answer

Let's break down why this is correct

Answer

The object starts to slide when the force pulling it down the surface becomes larger than the maximum static friction that can hold it. Static friction is equal to the coefficient of static friction times the normal force, which for a 270‑gram weight is \(mg\). If the slope or the surface is such that the downslope component of gravity exceeds this frictional force, the object can no longer stay at rest. For example, a 270‑gram block on a 30° incline with a static friction coefficient of 0. 3 will have a downslope force of about 1.

Detailed Explanation

The object starts moving when the downward pull from gravity is stronger than the maximum static friction that keeps it still. Other options are incorrect because Many think kinetic friction is higher than static friction, but it is usually lower or equal; The weight of the object does not shrink when it slides.

Key Concepts

Friction Forces
Weight and Motion
Static vs. Kinetic Friction
Topic

Friction Forces Analysis (Part 3)

Difficulty

medium level question

Cognitive Level

understand

Ready to Master More Topics?

Join thousands of students using Seekh's interactive learning platform to excel in their studies with personalized practice and detailed explanations.