A student wants to lift a 250 N bucket of water up from the bottom of a well using a wheel and axle. The wheel has a radius of 75 cm, and the axle has a radius of 20 cm. How much force will the student need to provide to the wheel to turn it and lift the bucket? A. 66.7 N
B. 37.5 N
C. 1667 N
D. 938 N

66.7 N

Explanation:

F(input) x r(input) = F(output) x r(output)

r=radius for wheel and axle problems

F=force

Because it asks for the force on the wheel, we would have the missing variable with the radius of the wheel. Let x be the missing output force. So by plugging in the givens we get:

(250 N) x (20 cm) = x (75 cm)

x= 66.7 N

  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