ICSE Class 11 Physics — Important Questions 2026

Einstein's mass-energy equivalence relation is ΔE = (Δm)c². If a substance loses a mass of 1 gram (0.001 kg), how much energy is released? (Speed of light c = 3 × 10⁸ m/s)

Which of the following correctly gives the relative strengths of the four fundamental forces of nature in increasing order?

The field particle associated with electromagnetic forces is called a photon. What is the field particle associated with strong nuclear forces?

In the radioactive decay: ₉₂U²³⁸ → ₉₀Th²³⁴ + ₂He⁴, which conservation law confirms that the total number of nucleons (238) is the same on both sides?

The Poisson's ratio of a material is 0.4. If a wire of this material is stretched so that its length increases by 0.2%, by what percentage does its radius decrease?

A steel wire (Y = 2 × 10¹¹ N/m²) of length 5 m and diameter 10⁻³ m supports a sphere of mass 8π kg and radius 0.1 m. The wire hangs from a ceiling 5.22 m high. When the sphere is swung as a pendulum, what is the approximate velocity at the lowest point? (g = 9.8 m/s²)

The interatomic force constant k of a solid material is related to its Young's modulus Y and equilibrium interatomic distance r₀ by which of the following relations?

In the stress-strain graph of a ductile material, the region between yield point C and the point D of maximum stress is called:

The density of a cube is calculated from ρ = m/l³. If the percentage error in the measurement of mass m is 2% and in the measurement of length l is 1%, what is the maximum percentage error in the calculated density?

1 parsec is approximately equal to how many light years?

How many significant figures are present in the number 0.006700?

The time period T of a simple pendulum is given by T = 2π√(l/g). If the length l is measured with 2% error and g is taken as exact, what is the percentage error in T?