Previous Year Questions on Most Important Chapters for JEE Mains Physics 2026
In this section, we shall look at some of the topics questions asked in previous years to help you get an idea of what kind of questions are asked. We shall go topic wise from the above table of topics:
1. A projectile is thrown with a velocity $u_0$ at an angle $\theta$ with the horizontal. The ratio of the rate of change of speed w.r.t. time at the highest point to that at the point of projection is
(A) $g \sin \theta$
(B) $-\mathrm{g} \sin \theta$
(C) zero
(D) g
Sol. C
$\frac{d v}{d t}(\text { at the top })=0$
As tangential acceleration at the top $=0$
$\frac{d v}{d t}(\text { at the starting point })=-g \sin \theta$
So, required ratio = zero.
2. In which case the wire has maximum expansion, if the same force is applied to each wire
a. $\mathrm{L}=500 \mathrm{~cm}, \mathrm{~d}=0.05 \mathrm{~mm}$
b. $\mathrm{L}=200 \mathrm{~cm}, \mathrm{~d}=0.02 \mathrm{~mm}$
c. $\mathrm{L}=300 \mathrm{~cm}, \mathrm{~d}=0.03 \mathrm{~mm}$
d. L $=400 \mathrm{~cm}, \mathrm{~d}=0.01 \mathrm{~mm}$
Ans. d)
Explanation:
$1 \alpha \frac{L}{r^2}(Y$ and $F$ are constant)
The maximum expansion occurs in the wire for which the ratio $\frac{\mathrm{L}}{\mathrm{r}^2}$ will be maximum.
3. At what temperature does the average translational kinetic energy of a molecule in a gas equal to the kinetic energy of an electron accelerated from rest through a potential difference of 5 volt.
(A) $386.5 \times 10^3 \mathrm{~K}$
(B) $3.865 \times 10^3 \mathrm{~K}$
(C) $.38 \times 10^3 \mathrm{~K}$
(D) $38.65 \times 10^3 \mathrm{~K}$
Explanation: (D)
K.E. of the electron is
$\begin{aligned} & 5 \mathrm{eV}=5 \times 1.6 \times 10^{-19} \mathrm{~J} \\ & \text { But } \quad \mathrm{K} . \mathrm{E} .=3 / 2 \mathrm{KT} \\ & \therefore 5 \times 1.6 \times 10^{-19}=3 / 2\left(1.38 \times 10^{-23}\right) \times \mathrm{T} \\ & \Rightarrow \mathrm{T}=\frac{5 \times 1.6 \times 10^{-19} \times 2}{3 \times 1.38 \times 10^{-23}} \\ & \Rightarrow \mathrm{~T}=38.65 \times 10^3 \mathrm{~K}\end{aligned}$
4. An adiabatic change in represented by the equation -
(A) $\mathrm{VP} \gamma=$ constant
(B) $\mathrm{PT} \gamma=$ constant
(C) $\mathrm{TV} \gamma=$ constant
(D) $\mathrm{PV} \gamma=$ constant
Explanation: (D)
This is the actual process equation
$\mathrm{PV} \gamma=\text { constant }$
5. The coefficient of static friction between a block of mass $m$ and an incline is $\mu_{\mathrm{s}}=0.3$. What can be the maximum angle $\theta$ of the incline with the horizontal so that the block does not slip on the plane?
Explanation:
Angle of repose $\theta=\tan ^{-1}(\mu)$
$\therefore \theta=\tan ^{-1}(0.3)=16.7^{\circ}$
6. A block rests on an inclined plane. The force of friction acting on the block is $(1 / n)$ times. The force required to move the block up the inclined plane with a uniform velocity $(n>1)$. If $\mu$ be the coefficient of friction, then the inclination of the plane with the horizontal is
(A) $\tan ^{-1}[(n-1) / \mu]$
(B) $\tan ^{-1}[\mu(n-1)]$
(C) $\tan ^{-1}[\mu /(n-1)]$
(D) $\tan ^{-1}(\mu)$
Explanation: $\mathbf{C}$
$\begin{aligned} & m g \sin \theta=\frac{1}{n}(m g \sin \theta+\mu m g \cos \theta) \\ & \Rightarrow m g \sin \theta(n-1)=\mu m g \cos \theta \\ & \Rightarrow \tan \theta=\frac{\mu}{(n-1)} \\ & \theta=\tan ^{-1}\left[\frac{\mu}{(n-1)}\right]\end{aligned}$
7. An electron of mass $m_e$, initially at rest, moves through a certain distance in a uniform electric field in time $t_1$. A proton of mass $m_p$, also initially at rest, takes time $t_2$ to move through an equal distance in this uniform electric field. Neglecting the effect of gravity, the ratio $t_2 / t_1$ is equal to
(A) 1
(B) $\left(\frac{\mathrm{m}_{\mathrm{e}}}{\mathrm{m}_{\mathrm{p}}}\right)^{1 / 2}$
(C) $\left(\frac{m_{\mathrm{z}}}{m_{\mathrm{e}}}\right)^{1 / 2}$
(D) $\left(\frac{\mathrm{m}_{\mathrm{p}}}{\mathrm{m}_{\mathrm{e}}}\right)$
8. A piece of copper and the other of germanium are cooled from the room temperature to 80 K , then which of the following would be a correct statement
(A) Resistance of each increase
(B) Resistance of each decrease
(C) Resistance of copper increases while that of germanium decrease
(D) Resistance of copper decrease while that of germanium increase
Sol. (D)
Resistance of conductors ( Cu ) decreases with decrease in temperature while that of semiconductors ( Ge ) increases with decrease in temperature.
9. Two capacitors are first connected in parallel and then in series. If the equivalent capacitances in the two cases are 16 F and 3 F, respectively, then capacitance of each capacitor is
(A) 16 F, 3 F
(B) 12 F, 4 F
(C) $6 \mathrm{~F}, 8 \mathrm{~F}$
(D) none of the above
10. A solid homogeneous sphere is moving on a rough horizontal surface, partly rolling and partly sliding. During this kind of motion of this sphere
(A) total kinetic energy is conserved
(B) angular momentum of the sphere about the point of contact with the plane is conserved
(C) only the rotational kinetic energy about the centre of mass is conserved.
(D) angular momentum about the centre of mass is conserved.
Explanation: B
When sphere partly rolls \& partly slides, frictional loss is there. Therefore, total mechanical energy cannot be conserved.
Since, all the forces passes through the instantaneous point of contact, their torque about this point is zero
$\Rightarrow$ Angular momentum about that point (not about the mass centre) remains constant.
For more practice solve JEE Main 10 Mock test according to latest pattern.
