A choke is preferred to resistance for limiting current in AC circuit because:

1. choke is cheap
2. there is no wastage of power
3. choke is compact in size
4. choke is a good absorber of heat

Subtopic:  LR circuit |
 59%
Please attempt this question first.
Hints

The velocity-time curve for a body projected vertically upwards is:
1. parabola
2. ellipse
3. hyperbola
4. straight line

Subtopic:  Graphs |
Please attempt this question first.
Hints

If \(r_1\) and \(r_2\) are the radii of the atomic nuclei of mass numbers \(64\) and \(125\) respectively, then the ratio \(\frac{r_1}{r_2}\) is:
1. \(\frac{64}{125}\)
2. \(\sqrt{\frac{64}{125}}\)
3. \(\frac54\)
4. \(\frac45\)

Subtopic:  Various Atomic Models |
 66%
From NCERT
Please attempt this question first.
Hints
Please attempt this question first.

advertisementadvertisement

The ionization energy of \(\mathrm{Li^{2+}}\) is equal to:
1. \(9hcR \)
2. \(6hcR\)
3. \(2hcR\)
4. \(hcR\)

Subtopic:  Bohr's Model of Atom |
 60%
Please attempt this question first.
Hints

A current of \(5\) A is passing through a metallic wire of cross-sectional area \(4\times10^{-6}\) m2. If the density of charge carriers of the wire is \(5\times10^{26}\) m-3, then the drift velocity of the electrons will be:
1. \(1\times 10^2\) m/s
2. \(1.56 \times10^{-2}\) m/s
3. \(1.56 \times10^{-3}\) m/s
4. \(1\times 10^{-2}\) m/s

Subtopic:  Current & Current Density |
 61%
Please attempt this question first.
Hints

The numerical ratio of displacement to the distance covered is always:

1. less than one
2. equal to one
3. equal to or less than one
4. equal to or greater than one
Subtopic:  Distance & Displacement |
 82%
From NCERT
Please attempt this question first.
Hints
Please attempt this question first.

advertisementadvertisement

The principle of LASER action involves:

1. amplification of particular frequency emitted by the system
2. population inversion
3. stimulated emission
4. all of the above
Subtopic:  Spectral Series |
 57%
Please attempt this question first.
Hints

A train is moving towards the east and a car is along the north, both at the same speed. The observed direction of the car to the passenger and the train is:
1. east-north direction
2. west-north direction
3. south-east direction
4. none of the above

Subtopic:  Relative Motion in One Dimension |
Please attempt this question first.
Hints

Which of the following is a unipolar transistor?
1. p-n-p transistor
2. n-p-n transistor
3. field effect transistor
4. point contact transistor

Subtopic:  Transistor (OLD NCERT) |
Please attempt this question first.
Hints

advertisementadvertisement

A solid sphere and a hollow sphere of the same material and of the same size can be distinguished without weighing:

1. by determining their moments of inertia about their coaxial axes
2. by rolling them simultaneously on an inclined plane
3. by rotating them about a common axis of rotation
4. by applying equal torque on them

Subtopic:  Rolling Motion (OLD NCERT) |
 51%
Please attempt this question first.
Hints