Friction Problems and Analysis MCQ & Objective Questions
Friction is a fundamental concept in physics that plays a crucial role in various real-life applications and exam scenarios. Understanding friction problems and analysis is essential for students preparing for school exams and competitive tests. Practicing MCQs and objective questions on this topic not only enhances conceptual clarity but also boosts your confidence, helping you score better in exams.
What You Will Practise Here
Understanding the types of friction: static, kinetic, and rolling friction.
Key formulas related to frictional force and its calculations.
Applications of friction in everyday life and engineering.
Diagrams illustrating frictional forces and their effects.
Concepts of friction in inclined planes and motion.
Real-world problems involving friction and their solutions.
Important definitions and terminologies related to friction.
Exam Relevance
The topic of friction is frequently tested in various examinations, including CBSE, State Boards, NEET, and JEE. Students can expect questions that assess their understanding of frictional forces, calculations involving friction, and applications in different scenarios. Common question patterns include numerical problems, conceptual questions, and application-based scenarios that require a solid grasp of the principles of friction.
Common Mistakes Students Make
Confusing static friction with kinetic friction and their respective coefficients.
Neglecting the role of angle in inclined plane problems.
Misapplying formulas related to friction, especially in complex scenarios.
Overlooking the effects of surface roughness on frictional force.
FAQs
Question: What are the types of friction I need to know for exams? Answer: You should be familiar with static friction, kinetic friction, and rolling friction, as these are commonly tested in exams.
Question: How can I improve my understanding of friction problems? Answer: Regular practice of MCQs and objective questions on friction will help solidify your understanding and improve problem-solving skills.
Start solving practice MCQs on Friction Problems and Analysis today to test your understanding and enhance your exam preparation. Remember, consistent practice is key to mastering this important topic!
Q. A 100 kg crate is resting on a horizontal surface. If the coefficient of static friction is 0.5, what is the maximum static friction force?
A.
490 N
B.
500 N
C.
510 N
D.
520 N
Solution
The maximum static friction force Ff = μs * N = 0.5 * (100 kg * 9.81 m/s²) = 490.5 N.
Q. A 250 kg object is subjected to a horizontal force of 600 N. If the coefficient of friction is 0.5, will the object move?
A.
Yes
B.
No
C.
Depends on the surface
D.
Not enough information
Solution
The maximum static friction force Ff = μs * N = 0.5 * (250 kg * 9.81 m/s²) = 1226.25 N. Since the applied force (600 N) is less than the frictional force (1226.25 N), the object will not move.
Q. A block on an inclined plane has a mass of 10 kg and the angle of inclination is 30 degrees. What is the force of friction if the coefficient of kinetic friction is 0.2?
A.
5.88 N
B.
6.67 N
C.
7.84 N
D.
8.00 N
Solution
The normal force N = mg * cos(θ) = 10 kg * 9.81 m/s² * cos(30°) ≈ 84.87 N. The force of friction Ff = μk * N = 0.2 * 84.87 N ≈ 16.97 N.
Q. A box weighing 300 N is pushed with a force of 150 N. If the coefficient of kinetic friction is 0.4, will the box move?
A.
Yes
B.
No
C.
Depends on the surface
D.
Not enough information
Solution
The force of kinetic friction Ff = μk * N = 0.4 * 300 N = 120 N. Since the applied force (150 N) is greater than the frictional force (120 N), the box will move.
Q. If a car is moving at a speed of 20 m/s and the coefficient of friction between the tires and the road is 0.7, what is the maximum deceleration the car can achieve?
A.
14.7 m/s²
B.
19.6 m/s²
C.
9.81 m/s²
D.
7.0 m/s²
Solution
The maximum deceleration a car can achieve is given by a = μg, where g = 9.81 m/s². Thus, a = 0.7 * 9.81 m/s² ≈ 6.87 m/s².
Q. What is the angle of inclination at which the force of static friction equals the component of weight acting down the slope for a coefficient of static friction of 0.4?
A.
21.8 degrees
B.
22.5 degrees
C.
23.5 degrees
D.
24.0 degrees
Solution
The angle θ can be found using tan(θ) = μs. Thus, θ = arctan(0.4) ≈ 21.8 degrees.
Q. What is the coefficient of static friction if a 50 kg box requires a force of 200 N to start moving?
A.
0.4
B.
0.5
C.
0.6
D.
0.7
Solution
The coefficient of static friction (μs) can be calculated using the formula F = μs * N, where N is the normal force. Here, N = mg = 50 kg * 9.81 m/s² = 490.5 N. Thus, μs = F/N = 200 N / 490.5 N ≈ 0.4.
