The ratio of resolving powers of an optical microscope for two wavelengths ${\lambda }_1$=4000 $\stackrel{0}{A}$ and ${\lambda }_2=6000$ $\stackrel{0}{A}$ is:

1. 9:4

2. 3:2

3. 16:81

4. 8:27

Given below are two statements: 

A major breakthrough in the studies of cells came with the development of an electron microscope. This is because:

The distance of the moon from the earth is $3.8\times {10}^5 km$. The eye is most sensitive to light of wavelength 5500 Å. The minimum separation between two points on the moon that can be resolved by a 500 cm telescope will be:

1. 51 m                         

2. 60 m

3. 70 m                         

4. All the above

The ratio of resolving powers of an optical microscope for two wavelengths ${\lambda }_1=4000 \stackrel{o}{A } and {\lambda }_2=6000 \stackrel{o}{A}$ is:

1. 8:27

2. 9:4

3. 3:2

4. 16:81

The resolving power of a microscope can be increased by using:

1.  red light.
2.  blue light.
3.  oil between objective lens and object.
4.  both (2) and (3).

The graph between resolving power and accelerating potential V for an electron microscope is (P is resolving power):

1.		2.
3.		4.

Resolving power of a compound microscope:

1.  Depends on the wavelength of light as \(\propto\) $\lambda$

2.  Depends on the wavelength of light as \(\propto\) $\lambda$²

3.  Depends on the wavelength of light as \(\propto\) $\frac{1}{\lambda }$

4.  Depends on the wavelength of light as \(\propto\) $\frac{1}{{\lambda }^2}$

Assume that light of wavelength 600 nm is coming from a star. The limit of resolution of telescope whose objective has a diameter of 2 m is:

1. $1.83\times {10}^{-7}$ $rad$

2. $7.32\times {10}^{-7}$ $rad$

3. $6.00\times {10}^{-7}$ $rad$

4. $3.66\times {10}^{-7}$ $rad$

The resolving power of a compound microscope will be maximum when: