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See all →- A and B each have certain number of oranges. A says to B, “ if you give me 10 of your oranges, Suppose A has x no. of oranges and B has y no. of oranges. According to the given conditions, we have x+10=2(y−10)⇒x−2y+30=0 (i) and, y+10=x... 1
- std 10th maharashtra board science part 1 gravitation notes Answer: Gravitation (Std 10 Science Part 1, Chapter 1) - solved exercise notes. 1. Match the entries and rewrite them in correct rows Quanti... 2
- M.In two moles of acetaldehyde (CH3 CHO) calculate the following a. Number of moles of carbon b. Number of moles of hydrogen Answer: (a) 4 mol C, (b) 8 mol H, (c) 2 mol O, (d) 1.2044 × 10²⁴ molecules Molecular formula of acetaldehyde: CH₃CHO = C₂H₄O. One molecule (... 1
- Niobium forms bcc structure the density of niobium is 8.55 g/cm3 and length of unit cell edge Answer: In 0.5 g of niobium there are 1.62×10²¹ unit cells and 3.24×10²¹ atoms. Given: bcc so n = 2 atoms per unit cell, ρ = 8.55\ g cm⁻³, a... 2
- The density of iridium is 22.4 g/cm3 . The unit cell of iridium is fcc. Calculate the radius of iridium atom. Molar mass of iridium is 192.2 g/mol. Answer: Radius of iridium atom r ≈ 136\ pm (edge length a ≈ 385\ pm) Given: ρ = 22.4\ g cm⁻³, M = 192.2\ g mol⁻¹, fcc unit cell so n = 4 ato... 1
- E. A student used a carbon pencil to write his homework. The mass of this was found to be 5 mg. With the help of this calculate. Given: mass of carbon = 5mg = 5× 10⁻³ g Atomic mass of carbon=12u Solution :: a. The number of moles of carbon in his homework writing numbe... 1
Recently answered
See all →- With a neat circuit diagram, explain the operation of an NPN transistor as a switch. In such a circuit \(V_{CC}=12\) V, \(R_C=1\) kΩ, \(\beta=100\) and \(V_{CE(sat)}=0.2\) V; find the collector saturation current and the minimum base current needed t… Answer: I_(C(sat)) = 11.8\ mA and I_(B(min)) = 118\ μA. Circuit An NPN transistor is connected in common-emitter mode. The load (R_C, or a l... 1
- Draw the characteristics of a Zener diode and explain the application of a Zener diode as a voltage regulator. (asked in MU Dec 2025) Answer: in reverse bias the Zener current rises sharply at the breakdown voltage V_Z while the voltage stays almost constant; connected in r... 1
- Draw a labelled sketch of a DC motor and state the function of each main part. Explain back EMF. A 220 V DC shunt motor has an armature resistance of 0.5 Ω and draws an armature current of 20 A; find its back EMF. Answer: back EMF E_b = V - I_a R_a = 220 - 20 × 0.5 = 210\ V. Construction PartFunction Yoke (frame)Outer cast-iron or steel frame; gives me... 1
- State the condition for resonance in a series RLC circuit. A series circuit has \(R=10\ \Omega\), \(L=0.2\) H and \(C=50\ \mu\)F and is fed from a 100 V variable-frequency supply. Find the resonant frequency, the current at resonance, the quality fac… Answer: f_r=50.33 Hz, I₀=10 A, Q=6.32, BW =7.96 Hz, f₁=46.51 Hz, f₂=54.47 Hz. Condition for resonance: X_L=X_C, i.e. ω L=dfrac1ω C. Then the... 1
- A series circuit consists of a 20 Ω resistor, a 0.1 H inductor and a 50 μF capacitor connected across a 230 V, 50 Hz supply. Calculate (i) the impedance, (ii) the current and the expression for \(i(t)\), (iii) the power factor, (iv) active, reactive… Answer: Z=37.94\ Ω (capacitive), I=6.06 A, i=8.57sin(314.16t+58.19^°) A, pf =0.527 leading, P=734.8 W, Q=1184.8 VAR (capacitive), S=1394.1 V... 1
- A sinusoidal voltage of 230 V (RMS), 50 Hz is applied to a circuit. Write the equation for its instantaneous value and find the time taken, measured from the zero crossing (going positive), for the voltage to reach 200 V for the first time. Answer: v=325.27sin(314.16 t) V; the voltage first reaches 200 V at t≈2.11 ms. Step 1: Peak value and angular frequency. V_m=sqrt2 V_rms=sqr... 1
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- How to Use NEET Previous Year Questions: A 4-Month Plan A month-by-month plan to use NEET previous year questions: unit-wise practice, timed sectionals, full mocks, a mistake notebook and a syllab...
- NEET Previous Year Papers 2016–2025: What 10 Years of Questions Show We tagged 2,060 questions from official NEET papers 2016–2025. See which Physics, Chemistry and Biology units grew or shrank, and what staye...
- Topics Removed from the NEET Syllabus (and How Many Questions They Had) All topics removed from the NEET syllabus, with how many questions each had in official 2016–2025 papers, and how to practise old papers.