1
WB JEE 2026
MCQ (Single Correct Answer)
+1
-0.25
Change Language

From a tower of height $H$ ,a particle is thrown vertically upwards with a speed $u$ .The time taken by the particle to hit the ground is $n$ times that taken by it to reach the highest point of its path.The relation between $H, u$ and $n$ is

A

$2 g H=n^2 u^2$

B

$g H=(n-2)^2 u^2$

C

$2 g H=n u^2(n-2)$

D

$2 g H=u^2(n-2)^2$

2
WB JEE 2026
MCQ (Single Correct Answer)
+1
-0.25
Change Language

There is a ring of radius $r$ having linear charge density $\lambda$ and rotating with a uniform angular velocity $\omega$. The magnitude of the magnetic field produced by this ring at its own centre would be ( $\mu_0=$ permeability of air)

A

$\frac{\lambda \omega^2}{2-\mu_0}$

B

$\frac{\mu_0 \lambda^2 \omega}{\sqrt{2}}$

C

$\frac{\mu_0 \lambda \omega}{2}$

D

$\frac{\mu_0 \lambda}{2 \omega^2}$

3
WB JEE 2026
MCQ (Single Correct Answer)
+1
-0.25
Change Language

Three vectors $\vec{a}, \vec{b}$ and $\vec{c}$ are such that $|\vec{a}|=1,|\vec{b}|=2$ and $|\vec{c}|=4$ along with $\vec{a}+\vec{b}+\vec{c}=0$ .Then,the value of $4 \vec{a} \cdot \vec{b}+3 \vec{b} \cdot \vec{c}+3 \vec{c} \cdot \vec{a}$ will be

A

27

B

-26

C

-68 problem is wrong.

D

-34

4
WB JEE 2026
MCQ (Single Correct Answer)
+1
-0.25
Change Language

Two identical metal bars are heated in two different temperatures and allowed to cool in the same surroundings. Which one of the following figures correctly shows their cooling curves?

A

WB JEE 2026 Physics - Heat and Thermodynamics Question 1 English Option 1

B

WB JEE 2026 Physics - Heat and Thermodynamics Question 1 English Option 2

C

WB JEE 2026 Physics - Heat and Thermodynamics Question 1 English Option 3

D

WB JEE 2026 Physics - Heat and Thermodynamics Question 1 English Option 4