OnlineCBT Logo OnlineCBT

Physics · PYQ NEET UG 2021

हिन्दी

A convex lens 'A' of focal length 20 cm and a concave lens 'B' of focal length 5 cm are kept along the same axis with a distance 'd' between them. If a parallel beam of light falling on 'A' leaves 'B' as a parallel beam, then the distance 'd' in cm will be:

  1. 15
  2. 50
  3. 30
  4. 25

Correct answer · Option 1

15

Explanation

For a parallel beam to remain parallel after passing through the lens combination, the focal points must coincide. Thus, \( d = f_A - f_B = 20 - 5 = 15\text{ cm} \).
पता संपर्क करें

+91 7877547686

ई-मेल

onlinecbtportal@gmail.com

हेल्पलाइन नंबर

+91 7877547686


डाउनलोड करने के लिए क्लिक करें
Get it on Google Play

ऐप डाउनलोड करने
के लिए Google Play पर
उपलब्ध है

WhatsApp Chat