Explanation:
Given that,
The mean kinetic energy of the emitted electron, 
(a) The relation between the kinetic energy and the De Broglie wavelength is given by :



(b) According to Bragg's law,

n = 1
For nickel, 



As the angle made is very small, so such an electron is not useful in a Davisson-Germer type scattering experiment.
Answer:
Given: V = 220V, Pmin = 360W, Pmax = 840W
For minimum heating case:
We know that
Pmin = VI
360 = 220 X I
I = 1.63 amp
R = V/I
R = 220/1.63
R = 134.96ohms
For maximum heating case:
We know that
Pmax = VI
840 = 220 X I
I = 3.81 amp
R = V/I
R = 220/3.81
R = 57.74 ohms
Answer:
The helicopter was deformed and destroyed in the inelastic collision.
Explanation:
- When two object collide there exist two way of colliding: elastic collision and inelastic collision.
- Two terms are considered during the collision: kinetic energy and momentum.
- If both of these terms are conserved in any collision then there is no significant loss of property, this is called as elastic collision.
- If only momentum is conserved but kinetic energy is converted into other forms then it is inelastic collision. In inelastic collision, the energy is lost in the form of vibration, sound etc. causing the damage to colliding object.
- Hence the deformation of helicopter was due to inelastic collision.
Most of the problem depends on which object you observe. For the speed, take the absolute value of the derivative of the polynomial interpolation of position verses time.