You are on a rooftop and you throw one ball straight down and another straight up. the second ball, after rising, falls and also strikes the ground below.

if air resistance can be neglected and if your downward and upward initial speeds are the same, how will the speed of the balls compare upon striking the ground?

1. the speed of the second ball is smaller than that of the first one.

2. the speed of the second ball is larger than that of the first one.

3. they have same speed.

4. more information is needed

2 the speed of the second ball is larger than that of the first one

Explanation:

Using the equations of motion

The second ball was thrown up , on getting to its highest point V=0, H=1/2gt^2

The second ball was. Now has two heights , the distance from the rooftop and the height it reached when the ball was thrown up.

v^2= u^2+2a(H1+H2)

The first ball has a velocity of v^2=2gH

Therefore the second ball velocity is larger than the first ball

  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

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