E=(mV^2)/2
m=1000kg, V=20m/s
then, E=(1000kg*(20m/s)^2)/2
E=(1000*400)/2 J = 200000J
Answer:
The longest wavelength of light is 209 nm.
Explanation:
Given that,
Spring constant = 74 N/m
Mass of electron 
Speed of light 
We need to calculate the frequency
Using formula of frequency

Where, k= spring constant
m = mass of the particle
Put the value into the formula


We need to calculate the longest wavelength that the electron can absorb

Where, c = speed of light
f = frequency
Put the value into the formula



Hence, The longest wavelength of light is 209 nm.
Answer:
8.4 V
Explanation:
induced emf, e1 = 5.8 V
Magnetic field, B1 = 0.38 T
magnetic field, B2 = 0.55 T
induced emf, e2 = ?
As we know that the induced emf is directly proportional to the magnetic field strength.
When the other parameters remains constant then


e2 = 8.4 V
Thus, the induced emf is 8.4 V.
First of all, both are not a single sheet of atom. There are many layers of atoms, so the empty part gets beside each other, so there are less empty part. Secondly, there are so many atoms that the probability that they will have empty space at the same place necessary, is negligible.
This was something from logic.
The reason I was taught in my class was that only a limited number of electrons can be in a given orbit, so atoms cannot overlap each other.