Twenty seven drops of same size are charged at \(220~\text{V}\) each. They combine to form a bigger drop. Calculate the potential of the bigger drop:
1. \(1520~\text{V}\)
2. \(1980~\text{V}\)
3. \(660~\text{V}\)
4. \(1320~\text{V}\)

Subtopic:  Electric Potential |
 71%
Level 2: 60%+
NEET - 2021
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For the given circuit, the input digital signals are applied at the terminals \(A\), \(B\) and \(C\). What would be the output at terminal \(Y\)?
 

1.
2.
3.
4.
Subtopic:  Logic gates |
 59%
Level 3: 35%-60%
NEET - 2021
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A particle of mass \(m\) is projected with a velocity, \(v=kv_{e} ~(k<1)\) from the surface of the earth. The maximum height, above the surface, reached by the particle is:
(Where \(v_e=\) escape velocity, \(R=\) the radius of the earth)

1. \(\dfrac{R^{2}k}{1+k}\) 2. \(\dfrac{Rk^{2}}{1-k^{2}}\)
3. \(R\left ( \dfrac{k}{1-k} \right )^{2}\) 4. \(R\left ( \dfrac{k}{1+k} \right )^{2}\)
Subtopic:  Escape velocity |
 64%
Level 2: 60%+
NEET - 2021
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A car starts from rest and accelerates at \(5~\text{m/s}^{2}.\) At \(t=4~\text{s}\), a ball is dropped out of a window by a person sitting in the car. What is the velocity and acceleration of the ball at \(t=6~\text{s}?\) 
(Take \(g=10~\text{m/s}^2\))

1. \(20\sqrt{2}~\text{m/s}, 0~\text{m/s}^2\) 2. \(20\sqrt{2}~\text{m/s}, 10~\text{m/s}^2\)
3. \(20~\text{m/s}, 5~\text{m/s}^2\) 4. \(20~\text{m/s}, 0~\text{m/s}^2\)
Subtopic:  Projectile Motion |
 65%
Level 2: 60%+
NEET - 2021
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A series \(LCR\) circuit containing \(5.0~\text{H}\) inductor, \(80~\mu \text{F}\) capacitor and \(40~\Omega\) resistor is connected to \(230~\text{V}\) variable frequency AC source. The angular frequencies of the source at which power transferred to the circuit is half the power at the resonant angular frequency are likely to be:

1. \(46~\text{rad/s}~\text{and}~54~\text{rad/s}\)
2. \(42~\text{rad/s}~\text{and}~58~\text{rad/s}\)
3. \(25~\text{rad/s}~\text{and}~75~\text{rad/s}\)
4. \(50~\text{rad/s}~\text{and}~25~\text{rad/s}\)

Subtopic:  Different Types of AC Circuits |
 51%
Level 3: 35%-60%
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A particle moving in a circle of radius \(R\) with a uniform speed takes a time \(T\) to complete one revolution. If this particle were projected with the same speed at an angle \(\theta\) to the horizontal, the maximum height attained by it equals \(4R.\) The angle of projection, \(\theta\) is then given by:
1. \( \theta=\sin ^{-1}\left(\frac{\pi^2 {R}}{{gT}^2}\right)^{1/2}\) 2. \(\theta=\sin ^{-1}\left(\frac{2 {gT}^2}{\pi^2 {R}}\right)^{1 / 2}\)
3. \(\theta=\cos ^{-1}\left(\frac{{gT}^2}{\pi^2 {R}}\right)^{1 / 2}\) 4. \(\theta=\cos ^{-1}\left(\frac{\pi^2 {R}}{{gT}^2}\right)^{1 / 2}\)
Subtopic:  Projectile Motion |
 72%
Level 2: 60%+
NEET - 2021
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Three resistors having resistances \(r_1, r_2~\text{and}~r_3\) are connected as shown in the given circuit. The ratio \(\dfrac{i_3}{i_1}\) of currents in terms of resistances used in the circuit is:

1. \(\dfrac{r_1}{r_1+r_2}\)
2. \(\dfrac{r_2}{r_1+r_3}\)
3. \(\dfrac{r_1}{r_2+r_3}\)
4. \(\dfrac{r_2}{r_2+r_3}\)
Subtopic:  Kirchoff's Voltage Law |
 61%
Level 2: 60%+
NEET - 2021
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A point object is placed at a distance of \(60~\text{cm}\) from a convex lens of focal length \(30~\text{cm}\). If a plane mirror were put perpendicular to the principal axis of the lens and at a distance of \(40~\text{cm}\) from it, the final image would be formed at a distance of:

1. \(30~\text{cm}\) from the plane mirror, it would be a virtual image.
2. \(20~\text{cm}\) from the plane mirror, it would be a virtual image.
3. \(20~\text{cm}\) from the lens, it would be a real image.
4. \(30~\text{cm}\) from the lens, it would be a real image.
Subtopic:  Lenses |
 60%
Level 2: 60%+
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A uniform rod of length \(200~ \text{cm}\) and mass \(500~ \text g\) is balanced on a wedge placed at \(40~ \text{cm}\) mark. A mass of \(2~\text{kg}\) is suspended from the rod at \(20~ \text{cm}\) and another unknown mass \(m\) is suspended from the rod at \(160~\text{cm}\) mark as shown in the figure. What would be the value of \(m\) such that the rod is in equilibrium?
(Take \(g=10~( \text {m/s}^2)\)

                    

1. \({\dfrac 1 6}~\text{kg}\) 2. \({\dfrac 1 {12}}~ \text{kg}\)
3. \({\dfrac 1 2}~ \text{kg}\) 4.  \({\dfrac 1 3}~ \text{kg}\)
Subtopic:  Torque |
 60%
Level 2: 60%+
NEET - 2021
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In the product 
\(\vec{F}=q\left ( \vec{v}\times \vec{B} \right )=q\vec{v}\times \left ( B\hat{i}+B\hat{j}+B_0\hat{k} \right ).\) For \(q=1 \) and \(\vec{v}=2\hat{i}+4\hat{j}+6\hat{k} \)  and \(\vec{F}=4\hat{i}-20\hat{j}+12\hat{k},\) what will be the complete expression for \(\vec{B} \)?
1. \(8\hat{i}+8\hat{j}-6\hat{k}\)
2. \(6\hat{i}+6\hat{j}-8\hat{k}\)
3. \(-8\hat{i}-8\hat{j}-6\hat{k}\)
4. \(-6\hat{i}-6\hat{j}-8\hat{k}\)

Subtopic:  Lorentz Force |
 53%
Level 3: 35%-60%
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