Apendulum has a mass of 1.5 kg and starts at a height of 0.4 m. if it is released from rest, how fast is it going when it reaches the lowest point of its path? acceleration due to gravity is g = 9.8 m/s2.

Assuming the lowest point of its path is at a height of 0 m, I would use the concept of conservation of energy:

At the highest point, the pendulum has no kinetic energy since its velocity is zero, so the total energy at that point is:

At the lowest point the potential energy is zero since the height h = 0, and now the energy reads:


Since no energy is lost:


Solve for v: