How do I find the non-uniform speed of a circular object?

A particle is projected vertically upwards with a speed of 100 ms-1 from a point at a height of X meters above ground level. If the stone hits the ground 25 seconds later ,find h

What is the difference between intermolecular forces and bonds

The surface of some metals, such as iron, corrode when exposed to air. Explain how this affects the electrical conductivity of the metal (3)