JEE Main 2026 · 2 Apr · Shift 1 · Physics Q41

← JEE Main 2026 · 2 Apr · Shift 1

PhysicsSingle correct+4 / -1Question 41 of 75

Refer the figure given below. $\mu_1$ and $\mu_2$ are refractive indices of air and lens material. The height of image will be ________ cm.

$A 2 cm tall object at O on the axis, in air (μ₁ = 1), faces a spherical refracting surface with pole P; the material beyond P has μ₂ = 1.54. The surface is concave towards the object: its centre of curvature C lies on the object side, 20 cm from P, and O is 40 cm from P.$

0.5

1.2

0.25

Answer and worked solution

Official answer: A

Refraction at the surface (light from left; $u=-40$ cm; the centre is on the incident side, so $R=-20$ cm):
$\frac{1.54}v-\frac1{-40}=\frac{0.54}{-20}\implies\frac{1.54}v=-0.052\implies v\approx-29.6\text{ cm}.$

Magnification. $m=\dfrac{\mu_1v}{\mu_2u}=\dfrac{-29.6}{1.54(-40)}\approx0.48$ .

Image height. $2\times0.48\approx0.96\approx1$ cm (virtual, erect).

(A)

Topics:Refraction at spherical surfaces

← Previous question Next question →

JEE Main 2026 · 2 Apr · Shift 1, Physics question 41