<u>Answer:</u> The velocity of released alpha particle is 
<u>Explanation:</u>
According to law of conservation of momentum, momentum can neither be created nor be destroyed until and unless, an external force is applied.
For a system:

where,
= Initial mass and velocity
= Final mass and velocity
We are given:

Putting values in above equation, we get:

Hence, the velocity of released alpha particle is 
<span>Which electromagnetic waves have the shortest wavelengths and highest frequencies?
Gamma rays </span>
Answer:

Explanation:
We are given that
Diameter=d=
Thickness=
Radius=
Using 
Dielectric constant=8
Resistance =
Internal specific resistance=r=100 ohm cm=
Using 1 m=100 cm
Internal resistance per unit length=
Using 
Internal resistance per unit length=