The six metals have the work functions, w.
part a rank these metals on the basis of their cutoff frequency. rank from largest to smallest. to rank items as equivalent, overlap them.
part b rank these metals on the basis of the maximum wavelength of light needed to free electrons from their surface. rank from largest to smallest. to rank items as equivalent, overlap them.
part c each metal is illuminated with 400 nm (3.10 ev) light. rank the metals on the basis of the maximum kinetic energy of the emitted electrons. (if no electrons are emitted from a metal, the maximum kinetic energy is zero, so rank that metal as smallest.) rank from largest to smallest. to rank items as equivalent, overlap them.
cesium= w= 2.1 ev aliminium= w= 4.1 ev beryllium= 5.0 ev potassium= 2.3 ev platinium= w= 6.4 ev magnisium=w= 3.7 ev

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.

force required to detach it is given by

charges are taken to be fundamental charge

now we have

so above is the minimum distance at which it will detach

total distance/total time

(85 + 82)/(5+3)

167/8

20 just over