You want to describe the harmonic motion of a swing. you find out that it take 2 seconds for the swing to
complete one cycle. what is the swing’s period and frequency?

photocells convert light energy to electricity

force is mass*acceleration.

we have a very small mass: 11.4*0.001 kg

if we want 0.035n of force, we need an acceleration:

0.035 = 11.4*0.001*a

a = 0.035/(11.4*0.001) m/s^2