Answer:
Explanation:
initial angular velocity, ωo = 0 rad/s
angular acceleration, α = 30.5 rad/s²
time, t = 9 s
radius, r = 0.120 m
let the velocity is v after time 9 s.
Use first equation of motion for rotational motion
ω = ωo + αt
ω = 0 + 30.5 x 9
ω = 274.5 rad/s
v = rω
v = 0.120 x 274.5
v = 32.94 m/s
Answer:
Wavelength, 
Explanation:
It is given that,
Velocity of an electron, 
Mass of an electron, 
We need to find the wavelength of an electron. It can be calculated using the De- Broglie wavelength as :



So, the wavelength of an electron is
. Hence, this is the required solution.
Answer and Explanation:
Using Gauss's law,
If r>a
then charge enclosed in all the three cases is same as Q.
So Electric field for all three is same.
So {1,1,1}.
(b) r<a,
Charge enclosed in case of shell is zero since all charge is present on the surface. So E = 0.
Charge enclosed by incase of point charge is Q.
Charge enclosed in case of sphere is Qr3/a3 which is less than Q.
So ranking {2,3,1}