a drop of oil (volume 0.05cm3) is released from a medicine dropper on to the calm surface of a pond where it spreads out to cover an area of 40cm2. Assume that the oil film has a uniform thickness equal to the diameter of an oil molecule. CALCULATE the diameter of an oil molecule and express your answer in scientific notation to an appropriate number of sig. figs.
volume = pi*r^2*thickness
You know volume is 0.05cc.
pi*r^2 is the area and you know that is 40 cm^2
calculate thickness. Watch the number of significant figures. Post your work if you get stuck.
2 answers
A thin apron is used in dental offices to protect patients from harmful xrays. If the sheet measures 75.0 cm by 55.0 cm by .10cm and the density of lead is 11.3 g/cm3 what is the mass of the apron in grams?
0.05c