Doubtify – JEE Ki Taiyaari, Simple Bhasha Mein

  🔢 Matrices & Determinants | JEE Maths | Doubtify JEE 📌 Question: The number of all 3 × 3 matrices A , with entries from the set {-1, 0, 1} , such that the sum of the diagonal elements of AAᵀ is 3 , is: 🖼️ Question Image:

  📈 Acceleration as a Function of Distance – Motion in One Dimension | JEE Physics | Doubtify JEE 🧮 Question: The distance x covered by a particle in one-dimensional motion varies with time t as: x² = at² + 2bt + c . If the acceleration of the particle depends on x as x⁻ⁿ , where n is an integer, what is the value of n ? 🖼️ Question Image: ✅ Detailed Concept & Solution: This is a JEE-level conceptual problem involving the relation between distance, velocity, and acceleration — with a twist of functional dependence. We are given: x² = at² + 2bt + c — (1) To find acceleration and its dependency on x , let’s differentiate both sides of equation (1): Differentiate w.r.t. time t : 2x(dx/dt) = 2at + 2b ⇒ v = dx/dt = (at + b)/x — (2) Now differentiate velocity v w.r.t time to find acceleration: a = dv/dt = d/dt[(at + b)/x] Use quotient rule: a = [a·x - (at + b)(dx/dt)] / x² Plug dx/dt = (at + b)/x from (2): a = [a·x - (at + b)·((at + b)/x)] / x² ⇒ ...

  ⏱️ Acceleration-Time Graph – Find Time When Initial Velocity is Regained | JEE Physics | Doubtify JEE ❓ Question: The acceleration-time graph of a particle is as shown. At what time does the particle acquire its initial velocity again?

🔄 Circular Motion | Physics | Doubtify JEE

🧪 Question: The ratio of mass percent of C and H of an organic compound (CxHyOz) is 6:1. If one molecule of the above compound contains half as much oxygen as required to burn one molecule of compound CxHy completely to CO₂ and H₂O, then what is the empirical formula of the compound? 📌 Why This Question is Important: This question combines two highly testable concepts in JEE Chemistry – combustion analysis and empirical formula derivation . You’re not only working with mass percent ratio , but also applying oxygen balancing logic in a combustion reaction. Such questions are frequently seen in organic chemistry chapters , particularly under Basic Principles of Organic Chemistry and Stoichiometry . Mastering this helps you crack more complex analysis-based questions in JEE Mains and even Advanced . 💡 Concept Used: To find the empirical formula , we first convert the mass percent ratio of C and H into moles , assuming 100 g of substance. Then we apply a stoichiometric appr...

🧪 Kinematics – Motion in a Straight Line | Physics | JEE Mains 📌 Question: A stone is dropped from the top of a building.  When it crosses a point 5 m below the top , another stone starts to fall from a point 25 m below the top , and both stones reach the bottom of the building simultaneously . Find the height of the building . (Take g = 10 m/s²) 🖼️ Question Image: 🧠 Solution (Image): 🎥 Video Solution: 🔍 Why this Question is Important: This is a  classic conceptual question from Kinematics , commonly asked in  JEE Mains  and other engineering entrance exams. It checks your understanding of  relative motion ,  free fall , and  time equations of motion  – topics that are often mixed to form trick questions. 📩 Have a Doubt? Drop us a mail at  doubtifyqueries@gmail.com  or DM us on  Instagram . Stay consistent. Watch – Pause – Solve – Repeat. Team Doubtify is with you till the finish line! 💪

  🧪 Balance the Ionic Equation in Alkaline Medium: Cr(OH)₃ + IO₃⁻ → I⁻ + CrO₄²⁻ | Doubtify JEE 📌 Question: Balance the following ionic equation in alkaline medium : Cr(OH)₃ + IO₃⁻ → I⁻ + CrO₄²⁻ 🖼️ Question Image: 🧠 Solution (Image): 🎥 Video Solution: 🔍 Why this Question is Important: This is a frequently asked question from Redox Reactions , commonly seen in JEE Mains and Advanced exams. Knowing how to balance redox reactions in alkaline medium is a core skill every aspirant must master. 📩 Have a Doubt? Drop us a mail at doubtifyqueries@gmail.com or DM us on Instagram . Stay consistent. Watch – Pause – Solve – Repeat. Team Doubtify is with you till the finish line! 💪