21 A nearsighted person might correct his vision by wearing diverging thin lenses with a focal length of -45cm. When wearing such glasses, he looks not at the actual objects but at the virtual image of these objects formed by the glasses. Suppose the person looks at a 10cm-long pencil held vertically at a 4.5m distance from the lenses. Determine the image’s location and height (both in absolute value). A) 12cm and 0.72cm
P21 A nearsighted person might correct his vision by wearing diverging thin lenses
with a focal length of -45cm. When wearing such glasses, he looks not at the actual objects but at
the virtual image of these objects formed by the glasses. Suppose the person looks at a 10cm-long
pencil held vertically at a 4.5m distance from the lenses. Determine the image’s location and
height (both in absolute value).
A) 12cm and 0.72cm
B) 40cm and 2.50cm
C) 41cm and 0.91cm
D) 50cm and 3.00cm
P2-2) Two molecules are diffusing in a water solution held at the same
temperature T. Molecule A has three times the mass of molecule B. Molecule A has also
a mean free path that is half that of molecule B. Both need to diffuse over the same
distance (Xeff). How do the diffusion speeds compare? (Express your answer in terms of a
“A over B” ratio).
A) 0.71
B) 0.29
C) 0.56
D) 2.45
P2-2) Two molecules are diffusing in a water solution held at the same
temperature T. Molecule A has three times the mass of molecule B. Molecule A has also
a mean free path that is half that of molecule B. Both need to diffuse over the same
distance (Xeff). How do the diffusion speeds compare? (Express your answer in terms of a
“A over B” ratio).
A) 0.71
B) 0.29
C) 0.56
D) 2.45
Trending now
This is a popular solution!
Step by step
Solved in 2 steps
