Answer:
0.22mm
Explanation:
A far sighted person is a person suffering from long sightedness i.e such individual can only see far distant object clearly but not near distant object. The defect is corrected using convex lens.
Since convex lens is used, the focal (f) length of the lens is positive and the image distance (v) is also positive.
Using the lens formula,
1/f = 1/u + 1/v
Where u is the object distance = 0.35mm
v = 0.6mm
1/f = 1/0.35+1/0.6
1/f = 2.86 + 1.67
1/f = 4.53
f = 1/4.53
f = 0.22mm
The focal length of the contact lenses will be 0.22mm
The answer is a property of density. The higher the density, the higher the pressure at the bottom.
Pressure = mass / Area. So given that the 4 samples occupy the same area at the bottom, the mass is going to be the determining factor. Per given volume, mercury has the largest mass. The answer is A
a). for velocity, you must have a number, a unit, and a direction.
Yes. This one isn't bad. The 'number' and the 'unit' are the speed.
b). the si units for velocity are miles per hour.
No. That's silly.
'miles' is not an SI unit, and 'miles per hour'
is only a speed, not a velocity.
c). the symbol for velocity is .
You can use any symbol you want for velocity, as long as
you make its meaning very clear, so that everybody knows
what symbol you're using for velocity.
But this choice-c is still wrong, because either it's incomplete,
or else it's using 'space' for velocity, which is a very poor symbol.
d). to calculate velocity, divide the displacement by time.
Yes, that's OK, but you have to remember that the displacement
has a direction, and so does the velocity.
