Aweight lifter is trying to lift a 1500-n weight but can apply a force of only 1200 n on the weight. one of his friends him lift it all the way. what force was applied to the weight by the weight lifter's friend?

300 N

Explanation:

We have three forces acting on the object:

- W = 1500 N, downward: the weight of the object

- F1 = 1200 N, upward: the force exerted by the first man

- F2, upward: the force exerted by the friend

In order to lift the object, the sum of the two forces F1 and F2 must be at least equal to the weight of the object W. Therefore we can write

And from this equation, we can find the magnitude of F2:

  1.the balanced   chemical equation is as below

cu +   2 ag(no)₃ → cu(no₃)₂   +2 ag

2.the   much silver   produced   is   50.9 g

step 1: find the   moles of cu

moles =   mass÷   molar mass

  from periodic table the molar mass of cu = 63.5 g/mol

moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236   moles

step 2: use the mole ratio to determine the   moles of ag

from equation above   cu: ag   is 1: 2

therefore the moles of ag   =0.236   moles   x 2/1 =0.472   moles

step 3: find the mass   of ag

mass = moles x molar mass

from periodic table   the molar mass of ag =107.87 g/mol

mass   = 0.472   moles x 107.87 g/mol = 50.9 g

3.   the   much   silver   collected worth is   1.797 oz

  convert   50.9 g   to oz

that is   1 gram = 0.0353 oz

          50.9 grams =?   oz

by cross multiplication

={(50.9 grams x 0.0353 oz) / 1   gram}   =1.797 oz