7.A builder carrying 6 bricks climbs a ladder. The weight of each brick is 25 N and the builder climbs a vertical distance of 4 meters in 8 seconds. Calculate the power used to raise all the bricks.

The power used to raise all the bricks is 75 watts.

Explanation:

Given;

number of blocks = 6

weight of each block = 25 N

vertical distance climbed by the builder, d = 4m

time to climb the the vertical distance, t = 8 seconds

Weight of the 6 blocks, F = 6 x 25 N = 150 N

speed of the build, v = 4 / 8 = 0.5 m/s

The power used to raise all the bricks is calculated as;

P = Fv

P = (150)(0.5)

P = 75 watts.

Therefore, the power used to raise all the bricks is 75 watts.

  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

a.   mass number from atomic number