Light of wavelength 503 nm illuminates a round 0.2-mm diameter hole. A screen is placed 4.9 m behind the slit. What is the diameter of the central bright area on the screen in millimeters

30 mm

Explanation:

= Wavelength of light = 503 nm

d = Diameter of hole = 0.2 mm

D = Distance of screen from light source = 4.9 m

Diameter of the central bright area is given by

The diameter of the central bright area is 30 mm.

  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

the current is 0.6

voltage ÷ resistance = current

so 12 ÷ 20 = 0.6