# Physics

posted by .

5) You are pushing a 55 kg refrigerator along at a constant speed of 1.5 m/s using an applied force of 250 N when the floor type changes from tile to carpet. The carpet has a coefficient of static friction of 0.62 and a coefficient of kinetic friction of 0.54. Are you pushing with enough force to keep the refrigerator moving?

No, because the force of static friction is greater than the pushing force

None of these explanations is correct

Yes, because it is already moving, it doesn't matter if the surface type changes because all surfaces have the same coefficient values

No, because it is moving at a constant speed so the net force is zero.
i'm thinking it is the 3rd option.

• Physics -

What made you think it is the third option? Did you do some calculations to justify this?
For the time being, ignore the static friction, assuming as you said, the refrigerator is already moving.
The normal reaction, N, on the carpet is mg.
The minimum force, F, to keep the refrigerator moving at a uniform speed is μmg, where μ is the coefficient of kinetic friction.
Does F exceed the current applied force of 250 N? The answer will lead you to the correct answer.