Abox has a mass of 400 g. what minimum force is needed to lift it? if it is raised to a height of 6.0 m, how much work was done?

We know that the mass of the box is m = 400g, then the weight of the box is equal to the gravitational acceleration times the mass, this is:

w = -9.8*0.4N = 3.92N downwards

Where i used 0.4kg instead of 400g, because the units are easily calculated in kg than in grams. This calculation is obtained by knowing that 1000g = 1kg, then 400g is equal to (400/1000)kg

Now, if you want to lift the box, you need to cancel this force, so you should use a force of at least 3.92N upwards.

And the work is defined as the movement done by a force, and can be calculated as:

W = F*d

in this case the minimal force is F = 3.92N, and the distance is d = 6.0m

And we have W = 3.92N*6.0m = 23.52 joules

the box does not move because you need to use a force greater than 300 n. you are only using 50 n. it needs to at least be 301 n for the box to move because then it is an unbalanced force and it will move the way that the greater force is pushing it. if you use only 300 n it will be a balanced force and will not move because the force you are exerting on the   box is the same as its force.

hope this !

im sorry if i went too in depth, i am going to include a link to a video on khan academy that will explain this.   hope that you like the video and that it explains more in detail to you.

that is the link.

which piece of furniture will have the most inertia and give the furniture movers the most difficulty in moving?  

answer

a 75kg dining table