Question bank

Physics

A ball is thrown vertically upward with a speed of 20 m s⁻¹. Taking g = 10 m s⁻² and neglecting air resistance, the maximum height it reaches is

KinematicsClass XINEETJEE MainCBSE BoardKCETAnswer: 20 m

Physics

Resistors of 6 Ω and 3 Ω are connected in parallel across a 6 V battery of negligible internal resistance. The current drawn from the battery is

Current electricityClass XIINEETJEE MainKCETAnswer: 3 A

Physics

The de Broglie wavelength ($\lambda = h/p$) of an electron accelerated from rest through a potential difference of 100 V is approximately

Dual nature of matterClass XIINEETCBSE BoardAnswer: 0.123 nm

Physics

Three capacitors of 2 μF each are connected as shown: two in series, and that pair in parallel with the third. The equivalent capacitance between A and B is

CapacitanceClass XIINEETJEE MainKCET DiagramAnswer: 3 μF

Chemistry

Which of the following elements has the highest first ionisation enthalpy? (1) B (2) C (3) N (4) O

Classification of elementsClass XINEETCUETCBSE BoardAnswer: N (half-filled 2p)

Chemistry

The hybridisation of the central atom and the shape of XeF₄ are respectively

Chemical bondingClass XINEETJEE MainKCETJEE AdvancedAnswer: sp³d², square planar

Chemistry

Assertion (A): Phenol is a stronger acid than ethanol. Reason (R): The phenoxide ion is stabilised by delocalisation of its negative charge over the benzene ring.

Alcohols, phenols and ethersClass XIINEETCBSE BoardAnswer: A and R true, R explains A

Chemistry

In acidic medium, the number of moles of \ce{KMnO4} needed to oxidise 1 mole of \ce{Fe^2+} to \ce{Fe^3+} is $x \times 10^{-1}$. The value of x is ____.

Redox reactionsClass XIJEE MainAnswer: 2

Biology

In C₄ plants, the primary CO₂ acceptor in the mesophyll cells is

Photosynthesis in higher plantsClass XINEETCBSE BoardAnswer: phosphoenolpyruvate (PEP)

Biology

Match List I (hormone) with List II (source): (a) Glucagon (b) Thyroxine (c) Melatonin (d) Aldosterone — (i) Pineal gland (ii) Adrenal cortex (iii) α-cells of the islets of Langerhans (iv) Thyroid gland

Chemical coordinationClass XINEETAnswer: a-iii, b-iv, c-i, d-ii

Biology

In the given diagram of a section of the human heart, the chamber labelled X receives oxygenated blood from the lungs. Identify X.

Body fluids and circulationClass XINEETFoundationCBSE Board DiagramAnswer: left atrium

Biology

Statement I: Okazaki fragments are formed on the lagging strand during DNA replication. Statement II: DNA polymerase can synthesise DNA only in the 5′ → 3′ direction.

Molecular basis of inheritanceClass XIINEETAnswer: both statements correct