Download App

Light – Reflection and Refraction — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceLight – Reflection and Refraction1 Mark
MCQ
A student focussed the Sun rays using an optical device $'X\ ’$ on a screen $S$ as shown. From this it may be concluded that the device $'X\ ’$ is a $($select the correct option$)$
  • A
    Convex lens of focal length $10 \ cm.$
  • B
    Convex lens of radius of curvature $20 \ cm.$
  • ✓
    Convex lens of focal length $20 \ cm.$
  • D
    Concave mirror of focal length $20 \ cm.$
✓

Answer

Correct option: C.
Convex lens of focal length $20 \ cm.$
Light rays from infinity are converged at the focal point of the convex lens. Therefore, the focal length of the convex lens is $20 \ cm.$
Hence, the correct option is $C.$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q" from Light – Reflection and Refraction→Light – Reflection and Refraction — all question types→Science STD 10 question papers→CBSE Board STD 10 question papers→CBSE Board question paper generator→

Similar questions

While cooking, if the bottom of the utensil is getting blackened on the outside, it means that:
→
The characteristics transmitted from parents to offspring are present in :
→
The hormone which increases the fertility in males is called :
→
In order to obtain a magnification of, -0.75 with a convex lens of focal length 8cm, the object should be placed:
→
A drop of liquid sample was put on the $\ce{pH}$ paper, paper turned blue. The liquid sample must be of :
→
Which of the following colour of white light is least deviated by the prism?
→
Which of the following is not a biomass energy source?
→
A $ ........... $ property is how a substance behaves when it undergoes a chemical change, e.g. its flammability or $\ce{pH}$.
→
The constituent of biogas which makes it an excellent fuel is:
→
A car headlight bulb working on a 12V car battery draws a current of 0.5A. The resistance of the light bulb is:
→