A rock is thrown horizontally off a 20m tall cliff with a prosody of 20 m/s what is the final velocity of the rock on the impact ( magnitude and direction)?

28.3 m/s 45° below horizontal

Explanation:

Given in the y direction:

Δy = -20 m

v₀ = 0 m/s

a = -10 m/s²

Find: v

v² = v₀² + 2aΔy

v² = (0 m/s)² + 2 (-10 m/s²) (-20 m)

v = -20 m/s

In the x direction, acceleration is 0, so v = v₀ = 20 m/s.

The magnitude is found with Pythagorean theorem:

v² = (20 m/s)² + (-20 m/s)²

v = 28.3 m/s

The direction is found with trig:

θ = atan(-20 m/s / 20 m/s)

θ = -45°

  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