A21-kg child starts at the center of a playground merry-go-round that has a radius of 1.7 m and rotational inertia of 500 kg⋅m2 and walks out to the edge. the merry-go-round has a rotational speed of 0.20 s−1 when she is at the center. what is its rotational speed when she gets to the edge?

Explanation:

given,  

radius of merry - go - round = 1.7 m  

mass of children = 21 Kg

rotational inertia of merry go round = 500 Kg.m²

rotational speed = 0.2 s⁻¹

I₁ = 500 Kg.m²

I₂ = I₁ + m R²

I₂ = 500 + 21 x 1.7²

I₂ = 560.69 Kg.m²

using equation

  I₁ ω₁ = I₂ ω₂

 500 x 0.2  = 560.69 ω₂

  the grams     of oxygen gas   that can be produced     is 20.6   grams of o₂

calculation

2liclo₃ →   2 licl + 3 o₂

step 1:   find the moles of liclo₃

moles = mass÷ molar mass

from periodic table the molar mass of liclo₃ =6.9 +35.5   +(16 x3) =90.4 g/mol

moles=38.7 g÷90.4 g/mol=0.4281   moles

step 2:   use the   mole ratio   to calculate the moles of o2

from equation above, liclo₃: o₂   is 2: 3  

therefore the moles of   o₂=0.4281 moles x3/2 =0.6422   moles

step 3: find mass   of o₂

mass= moles x molar mass

from periodic table the   molar mass of   o₂ = 16 x2= 32 g/mol

mass=0.6422   moles   x   32 g/mol = 20.6 grams of o₂

causes

fossil fuels burn

cities become more industrialized

human population grows worldwide