For an object to be in equilibrium, it must be experiencing no acceleration. This means that both the net force and the net torque on the object must be zero.
Convert 10mm to metres = 0.01m
Wave speed = frequency *wavelength
= 4Hz*0.01m
= 0.04 m/s
Hope this helps
Why do teachers give such hard questions? anyways hopefully your question will get answered! (btw i also need the points but yeah gl!!!)
Particle kinetic energy and particle speed