A2 kilogram object falls a distance of 5 meters. how much potential energy does this object have before it falls? how much work is done on it by gravity as it falls

1) Potential energy before the fall: 98 J

The gravitational potential energy of an object is given by:

where m is the mass of the object, g is the gravitational acceleration and h the heigth of the object above the ground.

In this problem, m = 2 kg, g = 9.8 m/s^2 and h = 5 m: substituting into the equation, we find

2) Work done by gravity: 98 J

The work done by a force is given by:

where

F is the magnitude of the force

d is the displacement of the object

is the angle between the direction of the force and the displacement

In this problem:

d = 5 m

Therefore,

  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

massxgravity x heght=weightxheight= pe

4900=490xh

h=10