The equivalent capacitance of the circuit is:

1. \(200~\text{pF}\) 2. \(\dfrac{200}{3}~\text{pF}\)
3. \(200~\mu\text{F}\) 4. \(150~\text{pF}\)

Subtopic:  Combination of Capacitors |
 79%
Level 2: 60%+
Hints
Links

A \(12~\text{pF}\) capacitor is connected to a \(50~\text V\) battery. How much electrostatic energy is stored in the capacitor?
1. \(3.1\times10^{-8}~\text J\)
2. \(2.9\times10^{-8}~\text J\)
3. \(3.3\times10^{-8}~\text J\)
4. \(1.5\times10^{-8}~\text J\)

 
Subtopic:  Energy stored in Capacitor |
 85%
Level 1: 80%+
Hints
Links

A stone of mass \(m\) tied to the end of a string revolves in a vertical circle of radius \(R.\) The magnitude of net forces at the lowest and highest points of the circle directed vertically downwards are:
(\(T_1\) and denote the tension and speed at the lowest point. \(T_2\) and \(v_2\) denote corresponding values at the highest point.)
Lowest point Highest point
1. \(mg-T_1 \) \(mg+T_2 \)
2. \(mg+T_1\) \(mg+T_2\)
3. \(mg+T_1-\frac{mv^2_1}{R}\)
\(mg-T_2+\frac{mv^2_2}{R}\)
4. \(mg-T_1-\frac{mv^2_1}{R}\) \(mg+T_2+\frac{mv^2_2}{R}\)

Subtopic:  Non Uniform Vertical Circular Motion |
 54%
Level 3: 35%-60%
Hints
Links

advertisementadvertisement

A rocket with a lift-off mass of \(20,000\) \(\mathrm{kg}\) is blasted upwards with an initial acceleration of \(5~\mathrm{ms}^{-2}\). Then initial thrust (force) of the blast is:
(Take \(g=10\) \(\mathrm{ms}^{-2}\))
1. \(7 \times 10^5 \mathrm{~N} \)
2. \(0 \)
3. \(2 \times 10^5 \mathrm{~N} \)
4. \(3 \times 10^5 \mathrm{~N}\)

Subtopic:  Application of Laws |
 69%
Level 2: 60%+
Hints
Links

A short electric dipole has a dipole moment of \(16 \times 10^{-9} ~\text{C-}\text{m}. \) The electric potential due to the dipole at a point at a distance of \(0.6~\text{m}\) from the centre of the dipole situated on a line making an angle of \(60^{\circ}\) with the dipole axis is:
\(\left( \dfrac{1}{4\pi \varepsilon_0}= 9\times 10^{9}~\text{N-m}^2/\text{C}^2 \right) \)

1. \(200~\text{V}\) 2. \(400~\text{V}\)
3. zero 4. \(50~\text{V}\)
Subtopic:  Energy of Dipole in an External Field |
 69%
Level 2: 60%+
NEET - 2020
Hints
Links

What will be the reading of the spring balance in the given setup? (take \(g=10~\text{m/s}^2\) )
                

1. \(60~\text N\) 
2. \(40~\text N\)
3. \(50~\text N\) 
4. \(80~\text N\) 

Subtopic:  Spring Force |
 60%
Level 2: 60%+
Hints
Links

advertisementadvertisement

A point mass \(m\) is moved in a vertical circle of radius \(r\) with the help of a string. The velocity of the mass is \(\sqrt{7gr} \) at the lowest point. The tension in the string at the lowest point is:

1. \(6 \text{mg}\) 2. \(7 \text{mg}\)
3. \(8 \text{mg}\) 4. \( \text{mg}\)
Subtopic:  Non Uniform Vertical Circular Motion |
 64%
Level 2: 60%+
NEET - 2020
Hints
Links

The equivalent capacitance across \(A\) and \(B\) in the given figure is:

       

1. \( \dfrac{3}{2}C\) 2. \({C}\)
3. \( \dfrac{2}{3}{C}\) 4. \( \dfrac{5}{3}C\)
Subtopic:  Combination of Capacitors |
 79%
Level 2: 60%+
Hints
Links

If a charge \(Q\) is situated at the corner of a cube, the electric flux passing through all six faces of the cube is:

1. \(\frac{Q}{6\varepsilon_0}\) 2. \(\frac{Q}{8\varepsilon_0}\)
3. \(\frac{Q}{\varepsilon_0}\) 4. \(\frac{Q}{2\varepsilon_0}\)

Subtopic:  Gauss's Law |
 70%
Level 2: 60%+
AIPMT - 2000
Hints
Links

advertisementadvertisement

A rigid rod is placed against the wall as shown in the figure. When the velocity at its lower end is \(10\) ms-1 and its base makes an angle \(\alpha=60^\circ\) with horizontal, then the vertical velocity of its end \(\mathrm{B}\) (in ms-1) will be:
                  

1. \(10\sqrt{3}\) 2. \(\frac{10}{\sqrt{3}}\)
3. \(5\sqrt{3}\) 4. \(\frac{5}{\sqrt{3}}\)
Subtopic:  String Constraint |
 63%
Level 2: 60%+
AIPMT - 1998
Hints
Links