282923
The focal lengths of the objective and eye-piece of a telescope are respectively \(100 \mathrm{~cm}\) and \(2 \mathrm{~cm}\). The moon subtends an angle of \(0.5^{\circ}\) at the eye. If it is looked through the telescope, the angle subtended by the moon's image will be
282924
For having large magnifying power of a compound microscope
1 focal lengths of objective lens and eye lens should be small
2 length of the microscope tube should be small
3 focal length of objective lens should be large
4 focal length of eye lens should be smaller than the focal length of its objective lens
Explanation:
A: The total lens magnification of compound microscope is,
\(m=\frac{L D}{f_o f_e}\)
\(m\) will increase if \(\mathrm{f}_0\) and \(\mathrm{f}_{\mathrm{e}}\) are small,
For having the large magnification power of a compound microscope, the focal length of the objective lens and eye-piece should be small.
CG PET- 2004
Ray Optics
282925
A person is suffering from the defect astigmatism, it's main reason is
1 distance of the eye lens from retina is increased
2 distance of the eye lens from retina decreased
3 the eye lens is not spherical
4 power of accommodation of the eye is decreased
Explanation:
C: Astigmatism - A person suffering from this defect cannot simultaneously focus on both horizontal and vertical lines of a wire gauge. This defect arises due to the fact that the cornea is not perfectly spherical. This defect can be corrected by using cylindrical lenses.
CG PET- 2004
Ray Optics
282926
When diameter of the aperture of the objective of an astronomical telescope is increased, its
1 magnifying power is increased and resolving power is decreased
2 magnifying power and resolving power both are increased
3 magnifying power remains the same but resolving power is increased
4 magnifying power and resolving power both are decreased
Explanation:
C: Resolving power of a telescope \(=\frac{\mathrm{a}}{1.22 \lambda}\)
Where, \(\mathrm{a}=\) diameter of the objective
\(\lambda=\) wavelength of the light
Magnifying power of a telescope
\(m=\frac{f_o}{f_e}\)
Where, \(f_o\) and \(f_e\) are focal lengths of objective lens and eyepiece. Therefore, on increasing diameter of the objective lens magnifying power remains the same but resolving power is increased.
282923
The focal lengths of the objective and eye-piece of a telescope are respectively \(100 \mathrm{~cm}\) and \(2 \mathrm{~cm}\). The moon subtends an angle of \(0.5^{\circ}\) at the eye. If it is looked through the telescope, the angle subtended by the moon's image will be
282924
For having large magnifying power of a compound microscope
1 focal lengths of objective lens and eye lens should be small
2 length of the microscope tube should be small
3 focal length of objective lens should be large
4 focal length of eye lens should be smaller than the focal length of its objective lens
Explanation:
A: The total lens magnification of compound microscope is,
\(m=\frac{L D}{f_o f_e}\)
\(m\) will increase if \(\mathrm{f}_0\) and \(\mathrm{f}_{\mathrm{e}}\) are small,
For having the large magnification power of a compound microscope, the focal length of the objective lens and eye-piece should be small.
CG PET- 2004
Ray Optics
282925
A person is suffering from the defect astigmatism, it's main reason is
1 distance of the eye lens from retina is increased
2 distance of the eye lens from retina decreased
3 the eye lens is not spherical
4 power of accommodation of the eye is decreased
Explanation:
C: Astigmatism - A person suffering from this defect cannot simultaneously focus on both horizontal and vertical lines of a wire gauge. This defect arises due to the fact that the cornea is not perfectly spherical. This defect can be corrected by using cylindrical lenses.
CG PET- 2004
Ray Optics
282926
When diameter of the aperture of the objective of an astronomical telescope is increased, its
1 magnifying power is increased and resolving power is decreased
2 magnifying power and resolving power both are increased
3 magnifying power remains the same but resolving power is increased
4 magnifying power and resolving power both are decreased
Explanation:
C: Resolving power of a telescope \(=\frac{\mathrm{a}}{1.22 \lambda}\)
Where, \(\mathrm{a}=\) diameter of the objective
\(\lambda=\) wavelength of the light
Magnifying power of a telescope
\(m=\frac{f_o}{f_e}\)
Where, \(f_o\) and \(f_e\) are focal lengths of objective lens and eyepiece. Therefore, on increasing diameter of the objective lens magnifying power remains the same but resolving power is increased.
282923
The focal lengths of the objective and eye-piece of a telescope are respectively \(100 \mathrm{~cm}\) and \(2 \mathrm{~cm}\). The moon subtends an angle of \(0.5^{\circ}\) at the eye. If it is looked through the telescope, the angle subtended by the moon's image will be
282924
For having large magnifying power of a compound microscope
1 focal lengths of objective lens and eye lens should be small
2 length of the microscope tube should be small
3 focal length of objective lens should be large
4 focal length of eye lens should be smaller than the focal length of its objective lens
Explanation:
A: The total lens magnification of compound microscope is,
\(m=\frac{L D}{f_o f_e}\)
\(m\) will increase if \(\mathrm{f}_0\) and \(\mathrm{f}_{\mathrm{e}}\) are small,
For having the large magnification power of a compound microscope, the focal length of the objective lens and eye-piece should be small.
CG PET- 2004
Ray Optics
282925
A person is suffering from the defect astigmatism, it's main reason is
1 distance of the eye lens from retina is increased
2 distance of the eye lens from retina decreased
3 the eye lens is not spherical
4 power of accommodation of the eye is decreased
Explanation:
C: Astigmatism - A person suffering from this defect cannot simultaneously focus on both horizontal and vertical lines of a wire gauge. This defect arises due to the fact that the cornea is not perfectly spherical. This defect can be corrected by using cylindrical lenses.
CG PET- 2004
Ray Optics
282926
When diameter of the aperture of the objective of an astronomical telescope is increased, its
1 magnifying power is increased and resolving power is decreased
2 magnifying power and resolving power both are increased
3 magnifying power remains the same but resolving power is increased
4 magnifying power and resolving power both are decreased
Explanation:
C: Resolving power of a telescope \(=\frac{\mathrm{a}}{1.22 \lambda}\)
Where, \(\mathrm{a}=\) diameter of the objective
\(\lambda=\) wavelength of the light
Magnifying power of a telescope
\(m=\frac{f_o}{f_e}\)
Where, \(f_o\) and \(f_e\) are focal lengths of objective lens and eyepiece. Therefore, on increasing diameter of the objective lens magnifying power remains the same but resolving power is increased.
282923
The focal lengths of the objective and eye-piece of a telescope are respectively \(100 \mathrm{~cm}\) and \(2 \mathrm{~cm}\). The moon subtends an angle of \(0.5^{\circ}\) at the eye. If it is looked through the telescope, the angle subtended by the moon's image will be
282924
For having large magnifying power of a compound microscope
1 focal lengths of objective lens and eye lens should be small
2 length of the microscope tube should be small
3 focal length of objective lens should be large
4 focal length of eye lens should be smaller than the focal length of its objective lens
Explanation:
A: The total lens magnification of compound microscope is,
\(m=\frac{L D}{f_o f_e}\)
\(m\) will increase if \(\mathrm{f}_0\) and \(\mathrm{f}_{\mathrm{e}}\) are small,
For having the large magnification power of a compound microscope, the focal length of the objective lens and eye-piece should be small.
CG PET- 2004
Ray Optics
282925
A person is suffering from the defect astigmatism, it's main reason is
1 distance of the eye lens from retina is increased
2 distance of the eye lens from retina decreased
3 the eye lens is not spherical
4 power of accommodation of the eye is decreased
Explanation:
C: Astigmatism - A person suffering from this defect cannot simultaneously focus on both horizontal and vertical lines of a wire gauge. This defect arises due to the fact that the cornea is not perfectly spherical. This defect can be corrected by using cylindrical lenses.
CG PET- 2004
Ray Optics
282926
When diameter of the aperture of the objective of an astronomical telescope is increased, its
1 magnifying power is increased and resolving power is decreased
2 magnifying power and resolving power both are increased
3 magnifying power remains the same but resolving power is increased
4 magnifying power and resolving power both are decreased
Explanation:
C: Resolving power of a telescope \(=\frac{\mathrm{a}}{1.22 \lambda}\)
Where, \(\mathrm{a}=\) diameter of the objective
\(\lambda=\) wavelength of the light
Magnifying power of a telescope
\(m=\frac{f_o}{f_e}\)
Where, \(f_o\) and \(f_e\) are focal lengths of objective lens and eyepiece. Therefore, on increasing diameter of the objective lens magnifying power remains the same but resolving power is increased.
