Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • Medical
  • A pulse of light of duration  is absorbed completely by a small object initially

A pulse of light of duration 100 \mathrm{~ns} is absorbed completely by a small object initially at rest. The power of the pulse is 30 \mathrm{~mW} and the speed of light 3 \times 10^8 \mathrm{~m} / \mathrm{s}. The final momentum of the object is

Option: 1

\quad 0.3 \times 10^{-17} \mathrm{~kg} \mathrm{~ms}^{-1}


Option: 2

\quad 1.0 \times 10^{-17} \mathrm{~kg} \mathrm{~ms}^{-1}


Option: 3

3 \times 10^{-17} \mathrm{~kg} \mathrm{~ms}^{-1}


Option: 4

\quad 9.0 \times 10^{-17} \mathrm{kgms}^{-1}


Answers (1)

best_answer

Using Einstein mass-energy equation

{E}=\mathrm{mc}^2

E = power  \times time

\begin{aligned} & \mathrm{E}=30 \times 10^{-3} \times 100 \times 10^{-9}=\mathrm{mc}^2=\mathrm{m} \times\left(3 \times 10^8\right)^2 \\ & \mathrm{~m}=\frac{1}{3} \times 10-25 \\ \end{aligned}using {p}=\mathrm{mv}

\begin{aligned} & \mathrm{p}=\frac{1}{3} \times 10^{-25} \times 3 \times 10^8=10^{-17} \mathrm{kgm} / \mathrm{s} \end{aligned}

Posted by

Ritika Harsh

View full answer

NEET 2024 Most scoring concepts

    Just Study 32% of the NEET syllabus and Score up to 100% marks

Similar Questions

Trending Articles/News

anam-khan

Karnataka: NEET candidate dies by suicide; no note recovered
anam-khan

CBSE Re-evaluation Row: Dharmendra Pradhan seeks detailed report on technical failures
anam-khan

Before NEET, CMC Vellore’s unique MBBS admissions tested aptitude along with merit; paper-leak restarts debate

Latest Question