How to Calculate Velocity and Distance for Block on Slab with Friction

  • Thread starter Thread starter Beckaze
  • Start date Start date
  • Tags Tags
    Block Friction
Click For Summary
SUMMARY

The discussion focuses on calculating the final velocity and distance traveled by a block on a slab with friction. The block has a mass of 0.5 kg and an initial speed of 4 m/s, while the slab has a mass of 3.0 kg and a coefficient of kinetic friction of 0.2. The key takeaway is that linear momentum conservation must be applied due to the non-conservation of kinetic energy caused by friction. The initial approach using kinetic energy conservation was incorrect, and participants are encouraged to utilize momentum conservation for accurate calculations.

PREREQUISITES
  • Understanding of linear momentum conservation
  • Knowledge of kinetic friction and its effects on motion
  • Familiarity with basic physics equations for velocity and distance
  • Ability to apply principles of energy conservation in mechanics
NEXT STEPS
  • Study the principles of linear momentum conservation in collisions
  • Learn how to calculate work done by friction in mechanical systems
  • Explore the relationship between kinetic energy and friction in motion
  • Review examples of similar physics problems involving blocks and slabs
USEFUL FOR

Students studying physics, particularly those focusing on mechanics and dynamics, as well as educators looking for practical examples of momentum and friction applications.

Beckaze
Messages
2
Reaction score
0

Homework Statement


The problem says: A small block of mass Mb = 0.5 kg is placed on a slab with mass Ms = 3.0 kg. Initially the slab is at rest and the block has a speed of V(initial)= 4m/s. The coefficient of kinetic friction between the block and the slab is .2 and there is no friction between the slab and the horizontal surface. At some moment later, before the block reaches the right end of the slab, both the block and the slab have the same speed Vfinal.

A)Calculate Vfinal
B) Calculate the distance the slab has traveled at the moment it reaches Vfinal
C)Calculate the work done by friction on the slab from the beginning of its motion until it reaches Vfinal

Homework Equations



The Attempt at a Solution



A) I tried 1/2 Mb vinital^2 = 1/2 Mb+s Vfinal^2 and i got 1.511 m/s but I feel like I missed a step with the friction. I don't know if it comes into play with the velocity.
 
Physics news on Phys.org
Hello Beckaze,

Welcome to Physics Forums!

You are correct about missing something with the friction. Because of the friction, kinetic energy is not conserved. In short, your attempted solution for part A is not valid. :frown:

On a positive note, you know that linear momentum is conserved, so you might want to start with that, for part A. :smile:
 
thanks so much for the help
 

Similar threads

Dynamics of a Block on top of a slab with friction between them
  • · Replies 33 ·
2
Replies
33
Views
2K
Block on top of moving slab, with a rough surface - When does v_b=v_s?
  • · Replies 27 ·
Replies
27
Views
2K
Linear Momentum of system of two blocks
  • · Replies 15 ·
Replies
15
Views
3K
Friction problem of a block sandwiched between 2 surfaces
  • · Replies 6 ·
Replies
6
Views
2K
Finding the work done by a block
  • · Replies 4 ·
Replies
4
Views
3K
Is Static Friction the Dominant Force in a Block on Top of a Slab System?
  • · Replies 4 ·
Replies
4
Views
3K
What Is the Direction of Force on a Dielectric Slab in a Capacitor?
  • · Replies 10 ·
Replies
10
Views
4K
Acceleration of Slab and Block: 58N Force
  • · Replies 2 ·
Replies
2
Views
5K
Why is the work done double its expected value? (conveyer belt)
  • · Replies 58 ·
2
Replies
58
Views
6K
Determine the friction force in a stacked block scenario
  • · Replies 23 ·
Replies
23
Views
3K