Question papers
GATE 2025 - Q1
Consider the matrix A below:$$\begin{bmatrix}2&3&4&5\\0&6&7&8\\0&0&\alpha&\beta//0&0&0&\gamma \end{bmatrix}$$
Correct Answer: Option B
Charge of an electron is $-1.602×10^{-19}\;C$
RPSC Lecturer - Q2
🌾The electric flux density is given $$D=(2y^2+z)I_x+4xyI_y+xI_z\;c/m^2$$ The volume charge density at point $(-1,\; 0,\; 3)$ is
a) $0\;c/m^3$
b) $-2\;c/m^3$
c) $-4\;c/m^3$
d) $-8\;c/m^3$
RPSC Lecturer - Q3
🌾The work done by a force $$F=4I_x-3I_y+2I_z\;m$$ in giving a $1\;nC$ charge a displacement of $10I_x+2I_y-7I_z\;m$ is
a) $103\;nJ$
b) $60\;nJ$
c) $40\;nJ$
d) $20\;nJ$
Correct Answer: Option D
One coulomb of charge equals
$$-1C=6.24×10^{18}\;e^-$$
‘n’ coulombs of charge equals,$$-nC=n×6.24×10^{18}\;e^-$$
Hence, $-3.941\;C$ equals, $$=3.941×6.24×10^{18}\;e^-$$ $$=24.59×10^{18}\;e^-$$ $$=2.459×10^{19}\;e^-$$
RPSC Lecturer - Q4
🌾If a vector field P is solenoidal, which of this is true?
a) $\oint_s P.ds=0$
b) $\oint_l P.dl=0$
c) $\nabla× (P)=0$
d) $\nabla×P\neq0$
Correct Answer: Option A and C
Unit of charge is coloumb.
Since $I=Q/t$ and $Q=It$, the unit of charge is also ampere-seconds
RPSC Lecturer - Q5
🌾The boundary condition valid at the boundary between two dielectrics $1$ and $2$ is
a) $E_{t1}=E_{t2}$
b) $E_1=E_2$
c) $D_{n1}=D_{n2}$
d) both A and C
Correct Answer: Option B
Current flow is nothing but the rate of flow of charge $$I=\frac{Q}{t}$$
RPSC Lecturer - Q6
🌾The magnetic field at any point on the axis of a current carrying circular coil will be
a) perpendicular to the axis
b) parallel to the axis
c) at an angle $45^{\circ}$ with the axis
d) zero
Correct Answer: Option B
Current flow is nothing but the rate of flow of charge $$I=\frac{Q}{t}$$
RPSC Lecturer - Q7
🌾Which of these statements is not characteristic of a static magnetic field?
a) It is conservative
b) It is solenoidal
c) It has no sink or sources
d) Magnetic flux lines are always closed
Correct Answer: Option B
Charge of an electron is $-1.602×10^{-19}\;C$
RPSC Lecturer - Q8
🌾Which of the following is zero?
a) grad div A
b) div gradient V
c) div curl A
d) curl curl A
Correct Answer: Option B
Charge of an electron is $-1.602×10^{-19}\;C$