ems

who discover oil drop

robert milk 1902

wo discovered cathod ray

JJ-thomas

who discovered golf foil

ernest rutheford 1980

why Millikan could not have determined the mass of a neutron in his famous oil drop experimen

because the electron force would not be able to pull the drops upwards because a neutrons is uncharged. The forces of gravity would be the only force acting on the drops, so there would be no way to suspend them.

explain why William Crookes could not have discovered the true charge-to-mass ratio of the electron using an electric field, whereas J.J. Thomson did."

Crookes could not get a good vacuum inside his tubes. The remaining air molecules became ionized by the cathode rays, which shielded the beam from external electric fields and prevented deflection. J.J. Thomson succeeded because he built much stronger vacuum pumps, removing the air molecules so the rays could be deflected by electric plates to prove they were negative particles.

Briefly explain why Rutherford could not have discovered the atomic nucleus if he had used a beam of neutrons instead of alpha (\(\alpha \)) particles in his gold foil experiment.

Rutherford's experiment relied on the electrostatic repulsion (positive pushing away positive) between the positive alpha particles and the positive gold nucleus to cause large-angle deflections. Because neutrons have no charge, they would not be repelled by the positive nucleus. Instead, they would pass straight through the atom or collide directly with no scattering, making it impossible to detect the charged nucleus.

when looking for energy and given wavelength use

E=hc/wavelenght

when looking for energy and given frequency use

E=hv

when calculating wavelenght when ur given energy use

wavelenght= hc/e

when calculating wavelngth and ur given frequency use

wavelength c/v

when frequency increases what will happen to the wavelength

the wavelenght will decreases because frequency and wavelength are inversely proportional

when frequency increases what will happen to energy

the energy also increases because frequency and energy are directly proportional