Question

Structures and Forces - What is force and external forces.

Question 1) Jacob and Ravleen are moving furniture. They need to move the filing cabinet over 6 feet and it is very heavy. Jacob wants to apply force and push it by putting his hands on point A because he thinks it would be easier to move it from the top as there is less weight on the top. Ravleen says it's better to push at point B because the center of gravity is lower. Which person is correct and EXPLAIN why and what may happen if it is pushed in the wrong spot.

Answer 1

The restoring force that prevents the furniture from tipping over when pushing the furniture towards the right, F= W × D

Where;

W = The weight of the furniture

D = The horizontal distance from the center of gravity of the furniture, CG and the to the lower right corner of the furniture

Given that A > D, for the furniture to tip over when pushing above the CG, we have;

F1 × A ≤ W × D

∴ F1 << W or for a force much smaller than W, the weight of the furniture applied above the center of gravity, the furniture will tip over

However when the force F2 is applied, where C < D, we have for no tipping over;

F2 × C ≤ W × D, therefore, given that C < D, when a force much higher than the weight, W, is applied at F2, the furniture will remain upright

Therefore, it is better push at a point lower than or equal to the center of gravity, whereby the point B is lower than the center of gravity, it is better to push at point B, Ravleen is correct and it is better to push at point B because the center of gravity is lower

If the furniture is pushed at the wrong spot it may tip over

Please see attached drawing

Step-by-step explanation: