Calculating the Force Needed to Push a Sofa Up an Inclined Plane

[aesoccer11]

Homework Statement

1. Suppose you needed to push a 1,500-N sofa up a frictionless ramp with a 30° angle. How much force would you have to apply to the sofa?

Homework Equations

f=ma

The Attempt at a Solution

I know that to find force you need to use the equation f=ma but I am not sure how I would go about finding the acceleration to do this problem. I know that the mass is 1,500 N.

 

[Orodruin]

Do you need to accelerate the sofa or is it sufficient to push it up with constant velocity? What forces apart from your pushing force act on the sofa?

I know that the mass is 1,500 N.

Do not confuse mass with weight. Mass is measured in kg or other units of mass. Weight is measured in units of force such as N.

 

[aesoccer11]

Would using Newton's Second Law to find acceleration be appropriate?
ax=-gsinθ
ax= (-9.81) sin(30)
ax= 4.91 m/s^2

 

[Chandra Prayaga]

That formula for acceleration is not correct unless there is no other force (such as your push) is acting on the sofa, other than gravity, and there is no friction. The question by Orodruin is the relevant one. You should specify all the forces, draw a free body diagram, and then use Newton's second law.