Register to reply

Block/Spring Problem (Kinetic Energy)

by lshine09
Tags: energ, kinetic energy, spring
Share this thread:
Mar9-10, 06:47 PM
P: 7
1. The problem statement, all variables and given/known data

A 13 kg block on a horizontal surface is attached to a horizontal spring of spring constant k = 4.3 kN/m. The block is pulled to the right so that the spring is stretched 13 cm beyond its relaxed length, and the block is then released from rest. The frictional force between the sliding block and the surface has a magnitude of 100 N.

(a) What is the kinetic energy of the block when it has moved 4.8 cm from its point of release?

(b) What is the kinetic energy of the block when it first slides back through the point at which the spring is relaxed?

(c) What is the maximum kinetic energy attained by the block as it slides from its point of release to the point at which the spring is relaxed?f

2. Relevant equations

ElasticPotentialEnergy= 1/2ky^2

3. The attempt at a solution

I honestly don't know where to begin. I used the numbers I was given to find the elastic potential energy at the beginning and came up with 36.34 J... and now I am not sure what to do.

Us= (1/2)(4300N/m)(.13)^2
Us= (36.34J)
Phys.Org News Partner Science news on
New type of solar concentrator desn't block the view
Researchers demonstrate ultra low-field nuclear magnetic resonance using Earth's magnetic field
Asian inventions dominate energy storage systems
Mar9-10, 07:12 PM
HW Helper
ideasrule's Avatar
P: 2,322
Use the conservation of energy, remembering to account for the energy lost by friction.

Register to reply

Related Discussions
Work and Potential/Kinetic Energy (spring problem) Introductory Physics Homework 2
Block compresses spring, find coefficient of kinetic friction Introductory Physics Homework 1
Bullet hitting a block attached to a spring, with kinetic coefficient of friction. Introductory Physics Homework 7
Can't find mistake on Spring/block Energy problem Introductory Physics Homework 1
Block hits block with spring. Conserv of Energy and Momentum? Introductory Physics Homework 6