A lead bullet penetrates into a solid and melts. Assuming that \(50\%\) of its kinetic energy was used to heat it, the initial speed of the bullet is: (the initial temperature of the bullet is \(25^\circ\mathrm{C} \) and its melting point is \(300^\circ\mathrm{C} \)). Latent heat of fusion of lead \(=2.5\times10^4~\mathrm{J/Kg}\) and specific heat capacity of lead \(=125~\mathrm{J/Kg-K}\).
1. \( 100 \mathrm{~m} / \mathrm{s} \)
2. \( 490 \mathrm{~m} / \mathrm{s} \)
3. \( 520 \mathrm{~m} / \mathrm{s} \)
4. \( 360 \mathrm{~m} / \mathrm{s}\)
 

Subtopic:  Calorimetry |
 55%
Please attempt this question first.
Hints

A quarter cylinder of radius \(R\) and refractive index \(1.5\) is placed on a table. A point object \(P\) is kept at a distance of \(mR\) from it as shown in the figure. For what value of \(m\) for which a ray from \(P\) will emerge parallel to the table?

1. \( 1 / 2 \)
2. \( 1 / 3 \)
3. \( 4 / 3 \)
4. \( 2 / 3\)

Subtopic:  Refraction at Plane Surface |
Please attempt this question first.
Hints

The graph \(\frac{1}{\lambda}\) and stopping potential (\(V\)) of three metals having work function \(\phi_1,~\phi_2\) and \(\phi_3\) in an experiment of the photoelectric effect is plotted as shown in the figure. Which one of the following statements is/are correct? [Here A. Is the wavelength of the incident ray] 
(i) Ratio of work functions \(\phi_1,\phi_2\) and \(\phi_3\) = 1: 2: 4 
(ii) Ratio of work functions \(\phi_1,\phi_2\) and \(\phi_3\) = 4: 2:1 
(iii) \(\tan\theta\propto\frac{hc}{e},\) Where h = plank’s constant, c = speed of light 
(iv) The violet-colour light can eject photoelectrons from metals 2 and 3
1.  (i), (iii)
2.  (i), (iv)
3.  (ii), (iii)
4.  (i), (ii) and (iv)
Subtopic:  Einstein's Photoelectric Equation |
Please attempt this question first.
Hints

advertisementadvertisement

The concentric, conducting spherical shells \(X,~ Y\) and \(Z\) with radii \(r, ~2r\) and \(3r\) respectively. \(X\) and \(Z\) are connected by a conducting wire and \(Y\) is uniformly charged to charge \(Q\) as shown in the figure. Charges on shells \(X\) and \(Z\) will be:

1. \(qx=\frac{Q}{4},qz=\frac{-Q}{6}\)
2. \(qx=\frac{-Q}{4},qz=\frac{Q}{4}\)
3. \(qx=\frac{Q}{4},qz=\frac{-Q}{4}\)
4. \(qx=\frac{-Q}{6},qz=\frac{Q}{4}\)

Subtopic:  Electric Potential |
 52%
Please attempt this question first.
Hints

The temperature of a gas is raised from \(27^\circ\mathrm{C}\) to \(927^\circ\mathrm{C}\). The root mean square speed:

1. gets halved
2. gets doubled
3. is \(\Big(\sqrt{\Big(\frac{927}{27}}\Big)\Big)\) times the earlier value
4. remains the same

Subtopic:  Types of Velocities |
 58%
Please attempt this question first.
Hints

A particle slides down on a smooth incline of inclination 30°, fixed in an elevator going up with an acceleration of 2 m/s2. The box of incline has a length of 4 m. The time taken by the particle to reach the bottom will be: 

1. \(\frac89\sqrt3s\)
2. \(\frac98\sqrt3s\)
3. \(\frac43\sqrt{\frac{\sqrt3}{2}}s\)
4. \(\frac34\sqrt{\frac{\sqrt3}{2}}s\)

Subtopic:  Pseudo Force |
 61%
To view explanation, please take trial in the course.
NEET 2023 - Target Batch - Aryan Raj Singh
Hints

advertisementadvertisement

A stone projected with a velocity \(u\) at an angle \(\Big(\frac{\pi}{2}-\theta\Big)\) with the horizontal reaches maximum height \(H_1\) When it is projected with velocity \(u\) at an angle with the horizontal, it reaches maximum height Hz. The relation between the horizontal range \(R\) of the projectile, \(H_1\) and \(H_2\) is:
1. \(R=4\sqrt{H_1H_2}\)
2. \(R=4({H_1-H_2})\)
3. \(R=4({H_1+H_2})\)
4. \(R=\frac{H^2_1}{H_2^2}\)

Subtopic:  Projectile Motion |
 64%
Please attempt this question first.
Hints

Two batteries of emf \(3~\text V\) and \(6~\text V\) with internal resistances \(2~\Omega\) and \(4~\Omega\) are connected in a circuit with a resistance of \(10~\Omega\) as shown in the figure. The current and potential difference between the points \(P\) and \(Q\) are:

1. \(\frac{3}{16}A~\text{and}~\frac{8}{15}V\)
2. \(\frac{16}{3}A~\text{and}~\frac{15}{8}V\)
3. \(\frac{3}{16}A~\text{and}~8~V\)
4. \(\frac{3}{16}A~\text{and}~\frac{15}{8}V\)

Subtopic:  Kirchoff's Voltage Law |
 56%
Please attempt this question first.
Hints

A light string passes over a frictionless pulley. To one of its ends, a mass of 8 kg is attached. To its other end, two masses of 7 kg each are attached. The acceleration of the system will be:

1.  10.2 g
2.  5.10 g
3.  20.36 g
4.  0.27 g
Subtopic:  Application of Laws |
 59%
Please attempt this question first.
Hints
Please attempt this question first.

advertisementadvertisement

A capillary tube of length \(L\) and radius \(v\) is connected with another capillary tube of the same length but half the radius in series. The rate of the steady volume flow of water through the first capillary tube under a pressure difference of \(p\) is \(V.\) The rate of the steady volume flow through the combination will be: (the pressure difference across the combination is \(p\))
1. \(17~V\)
2. \(\frac{16}{17}~V\)
3. \(\frac{V}{17}\)
4. \(\frac{17}{16}~V\)

Subtopic:  Capillary Rise |
Please attempt this question first.
Hints