For this problem you will need measurements of the position vs. time of a block sliding on a table, starting with some initial velocity, showing down, and coming to rest. If you do not have an appropriate laboratory setup for making these measurements, your instructor will provide you with such data. Analyze these data to determine the coefficient of friction and to see how well they support the assertion that the force of sliding friction is essentially independent of the speed of sliding.

Short Answer

Expert verified

The coefficient of friction is determined by using a position vs. time graph which is essentially independent of the speed of sliding.

Step by step solution

01

Significance of coefficient of friction

  • The force needs to resist the movement of an objectis known asfrictional force
  • The parameter gotten from theposition vs time graph is velocity. If theslope is deeper, thenquicker the movement is changing.
  • The ratio of friction force to normal force is defined as the coefficient of friction
  • The coefficient of kinetic friction is defined asthe ratio of kinetic friction force to the normal force.
  • The coefficient of kinetic friction is defined asthe ratio of static friction force to the normal force.
  • The coefficient of static friction is known as the limiting friction which has the maximum value.
  • The coefficient of kinetic friction has the magnitude of the constant force which has less than the limiting friction.

  • The coefficient of static frictionis equal to or greater than the coefficient of kinetic friction.
02

Determination of coefficient of friction using position vs. time

  • We have to set up an experiment for a block sliding on a table to measure the force of friction.
  • We have to start with some initial velocity, showing down, and coming to rest to measure a moving distance L
  • We have to draw the friction force F , on the y - axis , and Normal Force N on the x - axis .
  • The slope of that graph will indicate the coefficient of kinetic friction.
  • We have to find the + y component perpendicular to the slope and + x down the slope by using a coordinate system.
  • Then apply Newton’s second law.
  • The tangent of the angle where the object slides, is knowns as the coefficient of static friction.
  • Sliding friction does not have the same variables, so it is independent of the speed of the sliding.
  • Sliding friction depends upon the material and the weight of the object.

Hence, using the above method the coefficient of friction is determined by using a position vs. time graph which is essentially independent of the speed of sliding.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Young’s modulus for aluminum is 6.2×1010N/m2. The density of aluminum is 2.7g/cm3, and the mass of one mole (6.02×1023atoms)is 27g. If we model the interactions of neighbouring aluminum atoms as though they were connected by spring, determine the approximate spring constant of such a spring. Repeat this analysis for lead is: Young’s modulus for Lead 1.6×1010N/m2and the density of lead is 11.4g/cm3, and the mass of one mole is 207g. Make a note of these results, which we will use for various purposes later on. Note that aluminum is a rather stiff material, whereas lead is quite soft.

It is sometimes claimed that friction forces always slow an object down, but this is not true. If you place a box of mass 8kgon a moving horizontal conveyor belt, the friction force of the belt acting on the bottom of the box speeds up the box. At first there is some slipping, until the speed of the belt, which is 5m/s. The coefficient of kinetic friction between box and belt is 0.6. (a) How much time does it take for the box to reach this final speed? (b) What is the distance (relative to the floor) that the box moves before reaching the final speed of5m/s?

You hang a heavy ball with a mass of 14 kg from a gold wire 2.5 m long that is 2 mm in diameter. You measure the stretch of the wire, and find that the wire stretched 0.00139 m. (a) Calculate Young’s modulus for the wire. (b) The atomic mass of gold is 197 g/mole, and the density of gold is. Calculate the interatomic spring stiffness for gold.

Question:A certain metal with atomic mass 2 × 10−25 kg has an interatomic bond with length 2.1 × 10−10 m and stiffness 40 N/m. What is the speed of sound in a rod made of this metal?

Young’s modulus for aluminium is .The density of aluminium is ,and the mass of one mole is 27g. If we model the interactions of neighbouring aluminium atoms as though they were connected by spring, determine the approximate spring constant of such a spring. Repeat this analysis for lead is: Young’s modulus for Lead and the density of lead is , and the mass of one mole is 207g. Make a note of these results, which we will use for various purposes later on. Note that aluminium is a rather stiff material, whereas lead is quite soft.

See all solutions

Recommended explanations on Physics Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free