- AElectric fire
- BNeon street sign
- CRed traffic light
- DSun
Explanation:
Neon street sign gives a line emission spectrum.
When neon atoms gain enough energy to become excited, light is produced. Atom releases a photon when it returns to a lower energy state.
Therefore, the source associated with a line emission spectrum is the neon street sign.
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A particle has a mass 400 times than that of the electron and charge is double than that of a electron. It is accelerated by 5V of potential difference. Initially the particle was at rest, then its final kinetic energy will be
|
(a) 5 eV |
(b) 10 eV |
(c) 100 eV |
(d) 2000 eV |
The energy of a charged capacitor resides in
|
(a) The electric field only
|
(b) The magnetic field only |
|
(d) Neither in electric nor magnetic field |
(d) Neither in electric nor magnetic field |
In the circuit shown in figure the maximum output voltage V0 is
|
(a) 0 V |
(b) 5 V |
(c) 10 V |
(d) |
Four identical electrical lamps are labelled 1.5V, 0.5A which describes the condition necessary for them to operate at normal brightness. A 12V battery of negligible internal resistance is connected to lamps as shown, then

|
(a) The value of R for normal brightness of each lamp is (3/4) W |
|
(b) The value of R for normal brightness of each lamp is (21/4) W |
|
(c) Total power dissipated in circuit when all lamps are normally bright is 24W |
|
(d) Power dissipated in R is 21W when all lamps are normally bright |
In the given figure, equivalent resistance between A and B will be
|
(a) |
(b) |
(c) |
(d) |
The lead wires should have
|
(a) Larger diameter and low resistance |
|
(b) Smaller diameter and high resistance |
|
(c) Smaller diameter and low resistance |
|
(d) Larger diameter and high resistance |
A vertical wire kept in Z-X plane carries a current from Q to P (see figure). The magnetic field due to current will have the direction at the origin O along

|
(a) OX |
(b) |
(c) OY |
(d) |