JEE Main 2021 Question Paper (26-Feb-2021) (Shift 2)

Question 1

The trajectory of a projectile in a vertical plane is $ y = \alpha x - \beta x^{2} $, where $ \alpha $ and $ \beta $ are constants and  x & y are respectively the horizontal and vertical distances of the projectile from the point of projection. The angle of projection $ \theta $ and the maximum height attained $ H $ are respectively given by

Accepted Answer

$	an^{-1} \alpha, \frac{\alpha^{2}}{4 \beta}$

Answer

$ 	an^{-1} \alpha, \frac{4 \alpha^{2}}{\beta} $

Answer

$	an^{-1}\left(\frac{\beta}{\alpha}ight), \frac{\alpha^{2}}{\beta}$

Answer

$ 	an^{-1} \beta, \frac{\alpha^{2}}{2\beta} $

Question 2

The internal energy $ U $, pressure $ P $, and volume $ V $ of an ideal gas are related as $ U = 3PV + 4 $. The gas is

Accepted Answer

polyatomic only

Answer

either monoatomic or diatomic

Answer

monoatomic only

Answer

diatomic only

Question 3

Given below are two statements: Statement $\mathrm{I}$: A second's pendulum has a time period of $1$ seconds.Statement $\mathrm{II}$: It takes precisely one second to move between the two extreme positions. In the light of the above statements,choose the correct answer from the options given below

Accepted Answer

Statement $ \mathrm{I} $ is false but Statement $ \mathrm{II} $ is true

Answer

Both Statement $ \mathrm{I} $ and Statement $ \mathrm{II} $ are true

Answer

Both Statement $ \mathrm{I} $ and Statement $ \mathrm{II} $ are False

Answer

Statement $ \mathrm{I} $ is true but Statement $ \mathrm{II} $ is false.

Question 4

Draw the output signal $ Y $ in the given combination of gates.

Accepted Answer

""

Answer

Answer

Answer

Question 5

Find the peak current and resonant frequency of the following circuit (as shown in figure).

Accepted Answer

$0.2\mathrm{A}$ and $50\mathrm{Hz}$

Answer

$2 \mathrm{A}$ and $50 \mathrm{Hz}$

Answer

$0.2\mathrm{A}$ and $100 \mathrm{Hz}$

Answer

$2  \mathrm{A}$ and $100 \mathrm{Hz}$