JEE model questions and answers in English

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## JEE Model Questions (Physics, Chemistry, Mathematics)

Here are a few JEE model questions with answers and explanations across Physics, Chemistry, and Mathematics:

Physics:*

Question:

A ball is thrown vertically upwards with a velocity of 20 m/s. What is the maximum height reached by the ball? (Take g = 10 m/s²

(A) 10 m

( 20 m
(C) 30 m
(D) 40 m

Answer:

( 20 m

Explanation:

We can use the following equation of motion: v² = u² + 2as. Here, v = final velocity (0 m/s at the highest point), u = initial velocity (20 m/s), a = acceleration (-10 m/s² since gravity acts downwards), and s = displacement (the maximum height).

0 = (20)² + 2(-10)s
0 = 400 - 20s
20s = 400
s = 20 m

Chemistry:*

Question:

Which of the following is an example of a redox reaction?

(A) NaCl + AgNO₃ → AgCl + NaNO₃

( CuO + H₂ → Cu + H₂O

(C) HCl + NaOH → NaCl + H₂O
(D) CaCO₃ → CaO + CO₂

Answer:

( CuO + H₂ → Cu + H₂O

Explanation:

In this reaction, CuO is reduced (Cu gains electrons, oxidation state changes from +2 to 0) and H₂ is oxidized (H loses electrons, oxidation state changes from 0 to +1). This simultaneous oxidation and reduction makes it a redox reaction.

Mathematics:*

Question:

Find the value of ∫₀¹ x² dx.

(A) 0
( 1
(C) 1/3

(D) 2/3

Answer:

(C) 1/3

Explanation:

The integral of x² is (x³/3. Evaluating this from 0 to 1 gives us:

[(1)³/3] - [(0)³/3] = 1/3 - 0 = 1/3.

More Challenging Example (Physics):*

Question:

A projectile is launched at an angle of 30° above the horizontal with an initial speed of 50 m/s. What is the horizontal range of the projectile? (Take g = 10 m/s²

(A) 216.5 m

( 108.3 m
(C) 250 m
(D) 125 m

Answer:

(A) 216.5 m

Explanation:

The horizontal range R is given by the formula: R = (u²sin(2&theta)/g, where u is the initial speed, θ is the launch angle, and g is the acceleration due to gravity.

R = (50² * sin(2 * 30°) / 10
R = (2500 * sin(60°) / 10
R = (2500 * (√3/2)) / 10
R ≈ 216.5 m



These are just a few examples. JEE questions cover a wide range of topics and difficulty levels. It's important to practice extensively and consult resources like previous year's papers and textbooks to thoroughly prepare for the exam. You can also find more practice questions online on various educational websites. Remember to focus on understanding the concepts and problem-solving techniques rather than memorizing formulas.