Another Newton law theoroy question

[narutodemonki]

Homework Statement

pushing an armchair across a carpeted or at constant speed v you apply a force of 100N
if you push same chair at constant speed 2v(twice as fast) you mush push with a force?
a)100N
B)141N

The Attempt at a Solution

Newtons second law? if the net force acting on object is zero or if no force is acting on object..objects at rest will stay at rest and objects in uniform motion will stay in uniform motion in a constant velocity straight lien unless acted on by a non negative resultant force.

...since the speed is constant that means no force is being applied? but the initial force was 100N? and was 100N for a while until the 2v speed was reached?

 

[zhermes]

If the velocity is constant, that means that no net force is being applied. Which means that something is counteracting the 100N being applied, what force is that?

If you double the velocity, how will that resistive force respond? (look at how the equation for that particular resistive force varies with velocity)

 

[physhelper301]

It sounds like a friction problem, however I'm not sure you have given enough of the details to solve.

 

[narutodemonki]

It sounds like a friction problem, however I'm not sure you have given enough of the details to solve.

Well the question is straight from the practice section of the text. That is all the info they have given.

 

[zhermes]

Well the question is straight from the practice section of the text. That is all the info they have given.

Yes, for this type of problem (simplicity-wise), its enough information.