The mass of an electron is 9.11×10−31 kg9.11×10−31 kg. If the de Broglie wavelength for an electron in a hydrogen atom is 3.31×10−10 m3.31×10−10 m, how fast is the electron moving relative to the speed of light? The speed of light is 3.00×108 m/s3.00×108 m/s. Express your answer numerically as a percent.

The speed of electron is 0.73 % of the speed of light.

Explanation:

Given that,

Mass of the electron,

De- Broglie wavelength of the electron,

Speed of light,

The De Broglie wavelength of the electron is given by the formula as follows :

The electron moving relative to the speed of light is calculated as :

So, the speed of electron is 0.73 % of the speed of light. Hence, this is the required solution.

because growing process had stoped after 4-5 year

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.