This is an apparatus for studying the photoelectric effect. the work function of the material beinginvestigated is 3.810–19j. light of a wavelength 350 nm is incident on the material. what is the lowestvoltage needed between the cathode (c) and the anode (a) to stop any electrons ejected from the cathodefrom reaching the anode?

1.175 V

Explanation:

We are given that

Work function of the material= J

Wavelength of light=m

Energy of photon=Work function+Kinetic energy of electron

Where

=Wavelength of light

=Speed of light

Work function

=Small voltage

=Plank's constant

Substitute the values then we get

Hence, the lowest voltage needed between the cathode and the anode to stop any electrons ejected from the cathode from reaching the anode=1.175 V

see earlier answer

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.