Doubtclip is an AI tutor that turns any homework or exam doubt into a step-by-step whiteboard video lesson with diagrams, formulas, and voice explanation.

Which subjects and exams does it support?

It supports Physics, Chemistry, Mathematics/Calculus and related STEM doubts for school boards, JEE, NEET, and global high-school / undergrad practice.

How do I get a video solution?

Upload a photo of the question or paste the text, sign in, and Doubtclip generates a whiteboard-style explanation video you can watch and share.

Is Doubtclip available worldwide?

Yes. Doubtclip is a web app for students globally. Lessons are available in English and Hinglish.

Laws of Motion

JEE Main level, single correct, medium

121 of 210

Question 121 of 210

A spring whose unstrentches length is $l$ has a force constant $k.$ The spring is cut into two pieces of unstretches lengths ${l}_{1}$ and ${l}_{2}$ where, ${l}_{1}=n{l}_{2}$ and $n$ is an integer. The ratio ${k}_{1}/{k}_{2}$ of the corresponding force constants, ${k}_{1}$ and ${k}_{2}$ will be:

Show answer and solution

Answer: (D) $\dfrac{1}{n}$

Spring constants of the spring will be inversely proportional to length.

\dfrac{{k}_{1}}{{k}_{2}}=\dfrac{{l}_{2}}{{l}_{1}}=\dfrac{1}{n}

JEE Main question paper PDF

Open a shift to read the full paper on this page, or download it.

JEE Main 2025 Apr 2 Shift 1 question paper

Open Download PDF

Opening paper…

Explain it as a whiteboard videoStep-by-step, in Hinglish or English. Your first video needs no login.Solved it on paper but got it wrong?Upload a photo of your working. Mistake Doctor marks the exact line that broke.

See it move: Laws of motion, friction and pulleys simulationDrag the sliders and watch the numbers in this question change.

More Physics practice

JEE Main Physics practice question on Laws of Motion (Spring force), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.