Bob is pushing a box across the floor at a constant speed of 1.4 m/s, applying a horizontal force whose magnitude is 65 n. alice is pushing an identical box across the floor at a constant speed of 2.8 m/s, applying a horizontal force. (a) what is the magnitude of the force that alice is applying to the box? f = n (b) with the two boxes starting from rest, explain qualitatively what alice and bob did to get their boxes moving at different constant speeds. in order to keep the box moving twice as fast, alice had to apply a constant force that was twice as large as the force that bob applied. each initially applied a force bigger than static friction to get the box moving and accelerating, then when the desired final speed was achieved they reduced the force to make the net force zero.

a) 65 N

b) Each initially applied a force bigger than static friction to get the box moving and accelerating, then when the desired final speed was achieved they reduced the force to make the net force zero.

Explanation:

a) Here, both boxes are identical. They have different velocities but the velocities are constant hence the force Alice is applying is 65 N. Constant velocity means there is no acceleration.

b) The acceleration that Alice provided must have been different than that of Bob. But after reaching their desired speed they stopped accelerating. This would make the net force zero.

  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