I think it is known as a pulsar!
A projectile fired upward from the Earth's surface will usually slow down, come momentarily to rest, and return to Earth. For a certain initial speed, however it will move upward forever, with its speed gradually decreasing to zero just as its distance from Earth approaches infinity. The initial speed for this case is called escape velocity. You can find the escape velocity v for the Earth or any other planet from which a projectile might be launched using conservation of energy. The projectile of mass m leaves the surface of the body of mass M and radius R with a kinetic energy Ki = mv²/2 and potential energy Ui = -GMm/R. When the projectile reaches infinity, it has zero potential energy and zero kinetic energy since we are seeking the minimum speed for escape. Thus Uf = 0 and Kf = 0. And from conservation of energy,
Ki + Ui = Kf + Uf
mv²/2 -GMm/R = 0
∴ v = √(2GM/R)
This is the expression for escape velocity.
The Wavelength is the distance between the same points on two adjacent (neighbouring) disturbances (e.g. from crest to crest or from compression to compression) i.e. one full cycle of the wave.
Take a lamina with three holes near the periphery of the lamina, now suspend the lamina through them, one by one. Draw a line of equilibrium for each suspension point. The point of intersection of these three lines would be the centre of gravity.
