MCQ
The aperture of a telescope is made large, because
- ✓To increase the intensity of image
- BTo decrease the intensity of image
- CTo have greater magnification
- DTo have lesser resolution
✓
Answer
Correct option: A.
To increase the intensity of image
a
( a)For greater aperture of lens, light passing through lens is more and so intensity of image increases.
( a)For greater aperture of lens, light passing through lens is more and so intensity of image increases.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
Two condensers of capacities $1\,\mu F$ and $2\,\mu F$ are connected in series and the system is charged to $120\;volts$. Then the $P.D.$ on $1\,\mu F$ capacitor (in $volts$) will be
→A body of mass $10 kg$ is projected at an angle of $45^{\circ}$ with the horizontal. The trajectory of the body is observed to pass through a point $(20,10)$. If $T$ is the time of flight, then its momentum vector, at time $t =\frac{ T }{\sqrt{2}}$, is.
→$\left[\right.$ Take $\left.g=10 m / s ^{2}\right]$
The following diagram is an arrangement to view the interference pattern produced by a wedge of liquid between a microscope slide and a glass block. The interference pattern obtained is made of equally spaced parallel fringes. The fringe separation (or fringe width) may be decreased by some of the following actions (Consider one change at a time).
A vertical electric field of magnitude $4.9 \times 10^{5} N / C$ just prevents a water droplet of a mass $0.1\, g$ from falling. The value of charge on the droplet will be ........ $\times 10^{-9} \;C$ $\left(\right.$ Given $\left.g =9.8 m / s ^{2}\right)$
→Below are two statements. One is labeled as Assertion $(A)$ and the other as Reason $(R).$
→Assertion $(A):$ The property of an object that allows it to regain its original shape after the external force applied to it is removed is called elasticity.
Reason $(R):$ The restoring force depends on the intermolecular and interatomic forces in a solid.
In the context of the above statements, choose the most appropriate answer from the options given below:
Assume that a tunnel is dug along a chord of the earth, at a perpendicular distance $( R / 2)$ from the earth's centre, where $'R'$ is the radius of the Earth. The wall of the tunnel is frictionless. If a particle is released in this tunnel, it will execute a simple harmonic motion with a time period
→The mass number of nucleus having radius equal to half of the radius of nucleus with mass number $192$ is:
→The Young's modulus of a steel wire of length $6\,m$ and cross-sectional area $3\,mm ^2$, is $2 \times 11^{11}\,N / m ^2$. The wire is suspended from its support on a given planet. A block of mass $4\,kg$ is attached to the free end of the wire. The acceleration due to gravity on the planet is $\frac{1}{4}$ of its value on the earth. The elongation of wire is (Take $g$ on the earth $=10$ $\left.m / s ^2\right):$
→A body of mass $5 \,kg$ is moving with velocity of $\vec{v}=(2 i+6 \hat{j}) \,m / s$ at $t=0 \,s$. After time $t =2 \,s$, velocity of body is $(10 \hat{i}+6 \hat{j})$, then change in momentum of body is ......... $kg m / s$
→A radiowave has maximum electric field intensity of $10^{-4}\ V/m$ on arrival at a receiving antenna. The maximum magnetic flux density of such a wave is
→