ω=μkeq
μ= reduced mass
Springs are in series connection,
keq=k1+k2k1k2
keq=5kk×4k=54k
keq=54×20Nm−1=16Nm−1
μ=m1+m2m1m2=0.2+0.80.2×0.8=0.16kg
ω=0.1616=100=10
JEE Main 2021 — Physics Waves & Oscillations
2021integermedium
In the reported figure, two bodies AandB of masses 200g and 800g are attached with the system of springs. Springs are kept in a stretched position with some extension when the system is released. The horizontal surface is assumed to be frictionless. The angular frequency will be _______ rads−1 when k=20Nm−1.
Official previous-year question
Held on 25 Jul 2021 · Verified 6 Jul 2026.
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