MCQ
Dark lines on solar spectrum are due to
- ALack of certain elements
- BBlack body radiation
- ✓Absorption of certain wavelengths by outer layers
- DScattering
✓
Answer
Correct option: C.
Absorption of certain wavelengths by outer layers
Due to the absorption of certain wavelengths by the elements in outer layers of sun.
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
Four bodies $P, Q, R$ and $S$ are projected with equal velocities having angles of projection $15,30,45$ and 60 with the horizontal respectively. The body having shortest range is
→The quality factor of $\text{LCR}$ circuit having resistance $(R)$ and inductance $(L)$ at resonance frequency $(\omega)$ is given by
→Two batteries of e.m.f. $4 V$ and $8 V$ with internal resistances $1 \Omega$ and $2 \Omega$ are connected in a circuit with a resistance of $9 \Omega$ as shown in figure. The current and potential difference between the points $P$ and $Q$ are
→
A charge of magnitude $3 e$ and mass $2 m$ is moving in an electric field $\vec{E}$. The acceleration imparted to the charge is
→A mass $m$ is vertically suspended from a spring of negligible mass; the system oscillates with a frequency $n$. What will be the frequency of the system if a mass $4 m$ is suspended from the same spring
→100 coplanar forces each equal to $10 N$ act on a body. Each force makes angle $\pi / 50$ with the preceding force. What is the resultant of the forces
→The resistance of a $5 \mathrm{~cm}$ long wire is $10 \Omega$. It is uniformly stretched so that its length becomes $20 \mathrm{~cm}$. The resistance of the wire is
→The ratio of thermionic currents $(I / I)$ for a metal when the temperature is slowly increased $T_0$ to $T$ as shown in figure. ( $I$ and $I$ are currents at $T$ and respectively). Then which one is correct?
→
A person is standing in an elevator. In which situation he finds his weight less than actual when
The displacement equation of a particle is $x=3 \sin 2 t+4 \cos 2 t$. The amplitude and maximum velocity will be respectively
→