when the acceleration of a block in simple harmonic motion on a spring is zero, what other quantity is also zero?

Hi there!

When the acceleration of a block in SHM is 0 m/s², the NET FORCE must equal 0 N.

0 m/s² acceleration is obtained when the spring is at its equilibrium point, meaning that:

∑F = -kx (x = displacement from equilibrium point in meters)

If the block is at the equilibrium point, displacement = 0m, so:

∑F = -k(0) = 0 N

With Newton's Second Law, ∑F = ma. If the net force is 0 N, then there is no acceleration experienced by the block.

Thus, the other quantity that must be 0 is the block's NET FORCE.

it becomes positively charged by charging it