We shine light of three different wavelengths—333 nm, 430 nm, and 649 nm—on a metal surface. the observations for each wavelength, labeled a, b, and c, are: observation a: no photoelectrons are observed. observation b: photoelectrons with a kinetic energy of 159 kj/mol are observed observation c: photoelectrons with a kinetic energy of 48 kj/mol are observed

if the forces acting on an object are unbalanced, the object will accelerate in the direction of the net force on the object.

explanation:

this is best explained by having an understanding of newton's second law, which states that f=ma. you see, when the forces are unbalanced, net force (sum of all forces) is not zero. therefore making it necessary for the object to have an acceleration in the direction of the net force.