Q. The electric field is $100V/m$, at a distance of $20cm$ from the centre of a dielectric sphere of radius $10cm$. Then $E$ at $3cm$ distance from the centre of sphere is:

1. $100V/m$
2. $125V/m$
3. $120V/m$
4. $zero$

Q. Find equivalent resistance between X and Y

1. R
2. R/L
3. 2R
4. 5R

Q.

1. $\frac{I}{\sqrt{3}}$
2. $\sqrt{3}I$
3. $\frac{I}{3}$
4. $3I$

Q. Magnetic field at point O will be

1. $\frac{{\mu }_{0}l}{2R}interior$
2. $\frac{{\mu }_{0}l}{2R}exterior$
3. $\frac{{\mu }_{0}l}{2R}(1+\frac{l}{\pi })exterior$
4. $\frac{{\mu }_{0}l}{2R}(1-\frac{l}{\pi })interior$

Q. A sound source producing waves of frequency $300Hz$ and wavelength $1m$. Observer is stationary, while source is going away with the velocity $30m/s$, then apparent frequency heard by the observer is:

1. $270Hz$
2. $273Hz$
3. $383Hz$
4. $300Hz$

Q. A steel wire if $1m$ long and $1m{m}^2$ cross section area is hanged from rigid end when weight of $1kg$ is hang from it, then change in length will be
(Young's coefficient for wire $Y=2\times {10}^{11}N/m^2)$

1. $0.5mm$
2. $0.25mm$
3. $0.05mm$
4. $5mm$

Q. If prism angle $\alpha =1^o,\mu =1.54$, distance between screen and prism $\left(D\right)=0.7m$, distance between prism and source $a=0.3m,\lambda =180\pi nm$, then in Fresnal biprism find the value of $\beta$ (fringe width)

1. ${10}^{-4}m$
2. ${10}^{-3}mm$
3. ${10}^{-4}\times \pi m$
4. $\pi \times {10}^{-3}m$

Q. According to Bohr's model of hydrogen atom, relation between principal quantum number n and radius of stable orbit is

1. $r\propto \frac{1}{n}$
2. $r\propto n$
3. $r\propto \frac{1}{n^2}$
4. $r\propto n^2$

Q. A particle moves towards East for $2s$ with velocity $15m/s$ and move towards North for $8s$ with velocity $5m/s$. Then, average velocity of the particle is

1. $7m/s$
2. $10m/s$
3. $1m/s$
4. $5m/s$

Q. A ball is released from certain height which losses 50% if its kinetic energy on striking the ground, it will attain a height again.

1. $\frac{1}{4}$ of initial height
2. $\frac{3}{4}$ of initial height
3. $\frac{1}{2}$ of initial height
4. None of the above

Q. Linear density of a string of is $1.3\times {10}^{-4}kg/m$ and wave equation is $y=0.021sin(x+30t)$. Find the tension in the string where, x in meter and t in second.

1. 0.12 N
2. 0.21 N
3. 1.2 N
4. 0.012 N

Q. A charged particle is accelerated by a potential of 200V. If its velocity is $8.4\times {10}^{8}m/s$, then value of e/m for that particle in $C/kg$ is:

1. $17.6\times {10}^{16}$
2. $1.76\times {10}^{15}$
3. $14.5\times {10}^{12}$
4. $1.45\times {10}^{15}$

Q. Remaining quantity (in %) of radioacative element after 5 half lives is

1. 4.124%
2. 31.1%
3. 3.125%
4. 42.125%

Q. If the increase kinetic energy of a body 300%, then per cent increase in its momentum is

1. 50%
2. 300%
3. 100%
4. 150%

Q. The reason of current flow in p-n junction in forward bias is:

1. All of the above
2. Drifting of minority charge carriers
3. Diffussion of charge carriers
4. Drifting of charge carriers

Q. 50 g ice at $0^{o}C$ in insulator vessel, 50 g water of ${100}^{o}C$ is mixed in it, then final temperature the mixture is (neglect the heat loss)

1. $0^o<<T_m<{20}^{o}C$
2. ${10}^{o}C$
3. ${20}^{o}C$
4. Above ${20}^{o}C$

Q. When an open organ is dipped in water upto half of its height, then its frequency will become

1. half
2. double
3. remain same
4. four time

Q. Change in acceleration due to gravity is same upto a height $h$ from each other i.e. at the earth surface and below depth $x$, then relation between $x$ and $h$ is $(handx<<<R_e)$

1. $x=h$
2. $x=2h$
3. $x=\frac{h}{2}$
4. $x=h^2$

Q. Vibrations of rope tied by two rigid ends shown by equation $y=cos2\pi tsin2\pi x$, then minimum length of the rope will be

1. $\frac{1}{2}m$
2. $5m$
3. $2\pi m$
4. $1m$

Q. If we change the value of R, then

1. Voltage does not change on C
2. Voltage does not change on LC combination
3. Voltage change on LC combination
4. Voltage does not change on L

Q. Work function of a metal is $5.2\times {10}^{-18}J$, then its threshold wavelength will be

1. $736.7\mathring{A}$
2. $760.7\mathring{A}$
3. $301\mathring{A}$
4. $380.7\mathring{A}$

Q. Relation between wavelength of photon and electron of same energy is

1. ${\lambda }_{ph}<{\lambda }_e$
2. $\frac{{\lambda }_e}{{\lambda }_{ph}}=constant$
3. ${\lambda }_{ph}>{\lambda }_e$
4. ${\lambda }_{ph}={\lambda }_e$

Q. If applied torque on a system is zero, i.e., $\tau =0$, then which of the following must be zero?

1. $\omega =0$
2. $\alpha =0$
3. $J=0$
4. $F=0$

Q. Real power consumption in a circuit is least when it contains.

1. High R, low L
2. High R, high L
3. High R, low C
4. low R, high L

Q. A mass of 1 kg is suspended from a spring of force constant 400 N, executing SHM total energy of the body is 2J, then maximum acceleration of the spring will be

1. $4m/s^2$
2. $200m/s^2$
3. $40m/s^2$
4. $400m/s^2$

Q. An observer is approaching with velocity $\upsilon$ towards a light source. If the velocity of light is c, then velocity of light with respect to observer will be

1. $c-v$
2. $c$
3. $c+v$
4. $\sqrt{1-v^2/c^2}$

Q. Magnetic field of the earth is $H=0.3g$. A magnet is vibrating $5$ oscillations per min then the dippreciation required in the magnetic field of the earth of increase time period upto $10$ Oscillations per minute is

1. $0.6g$
   
2. $0.12g$
   
3. $0.9g$
   
4. $2.25g$
   

Q. When plate voltage in diode valve is increased from 100V to 150V. Then, plate increases from 7.5 mA to 12 mA, then dynamic plate resistance will be

1. $10k\Omega$
2. $11k\Omega$
3. $11.1k\Omega$
4. $15k\Omega$

Q. Two capacitors of capacities $C_1$ and $C_2$ are charged upto the potential $V_1$ and $V_2$ then condition for not flowing the charge between them when connected the capacitors, in parallel is

1. $C_1=C_2$
2. $C_1{V}_1=C_2{V}_2$
3. $\frac{C_1}{V_1}=\frac{C_2}{V_2}$
4. $V_1=V_2$

Q. Match the following.

	List I		List II
A.	Angular momentum	1.	$\left[M^{-1}{L}^2{T}^{-2}\right]$
B.	Torque	2.	$\left[M^1{T}^{-2}\right]$
C.	Gravitational constant	3.	$\left[M^1{L}^2{T}^{-2}\right]$
D.	Tension	4.	$M^1{L}^2{T}^{-1}]$

1. C-2, D-1
2. A-4, B-3
3. A-3, C-2
4. B-2, A-1