KEAM 2019 Physics and Chemistry Paper

A mass suspended by a massless spring is given in figure.Mass m is displaced by height h, then potential energy of spring and change in gravitational potential energy due to height
U‌spring ‌=‌

1

2

kx2=‌

1

2

kh2
and ‌‌U‌gravitation ‌=mgh
If the system is released, then both the energies converted into kinetic energy.
Hence, KE=‌

1

2

kh2+mgh
So, kinetic energy of mass is a linear combination of terms (‌

1

2

kh2 and mgh) involving h and h2.