Pushing a Box on Frictionless Floor: Worker's Force & Box's Weight

[steelydan8821]

Homework Statement

On a horizontal frictionless floor, a worker of weight 900N pushes horizontally with a force of 200N on a box weighing 1800N

Homework Equations

The Attempt at a Solution

I do not know where to start.

 

[PhanthomJay]

What's the question?

 

[steelydan8821]

As a result of the push:
A. the worker and box will both have an acceleration of 2.18m/s^2, but in opposite directions
B. The worker will accelerate at 1.09m/s^2 and the box will accelerate at 2.18m/s^2, but in opposite directions
C. The worker will accelerate at 2.18m/s^2 and the box will accelerate at 1.09m/s^2, but in opposite directions
D. The worker and box will both have an acceleration of 1.09m/s^2, but in opposite directions
E. The box will not move because the push is less than its weight

 

[PhanthomJay]

What have you tried so far?

 

[steelydan8821]

well i think the sum of the forces in the x direction must equal ma
Fx=ma
200N= ((1800N+900N)/9.81)*a
But this can't be right because the value for a doesn't fit the answers

 

[HallsofIvy]

As a result of the push:
A. the worker and box will both have an acceleration of 2.18m/s^2, but in opposite directions
B. The worker will accelerate at 1.09m/s^2 and the box will accelerate at 2.18m/s^2, but in opposite directions
C. The worker will accelerate at 2.18m/s^2 and the box will accelerate at 1.09m/s^2, but in opposite directions
D. The worker and box will both have an acceleration of 1.09m/s^2, but in opposite directions
E. The box will not move because the push is less than its weight

Do you mean "which of these is true"? Is so, it would have helped a lot if you had said that in your first post!

I don't see any need to do ANY calculation. One answer can be thrown out because it is just silly. The correct choice from the other 4 only requires recognizing that the worker has greater mass than the box!

 

[steelydan8821]

the worker has a mass of 900N the box has a mass of 1800N
1800>900