(a) what velocity must a helium atom (6.647 x 10^27 kg) have, to be diffracted by a film of silver atoms in which the spacing between atoms is 1.00 x 10-10 m?
(i) what is the wavelength requirement for radiation or an object (with resting mass) to undergo optimum diffraction around an (or between) object(s) ?
(ii) what relationship will you use to determine the velocity of helium traveling as a wave?
(b) electrons accelerated by a certain potential are diffracted by a thin film of gold. a beam of protons accelerated through the same potential are not diffracted by that same thin film of gold. briefly explain why this is so.

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.

i had this question and the answer was 3.15 miles.

martina travels from school to her mom's office. from there, she walks to school. after school, she walks to the library and then to a friends house before finally ending back at home. find martina's total distance traveled.

a) 0 miles  

b) 0.4 miles  

c) 1 mile  

d) 3.15 miles

the maxium height is 34m/s