The air would contract therefore the answer is the second choice.
Abiotic factors are the nonliving physical and chemical components of an ecosystem, while biotic factors are the living components of an ecosystem. Both types of factors affect reproduction and survival
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:
particle's potential energy = 70J
Explanation:
From conservation of energy; K1 + Ue1 = K2 + Ue2
where K1 and K2 are the kinetic energies at two positions and Ue1 and Uue2 are the electrical potential energies at two positions.
k1 = 10J, Ue1 = 100J
K2 = 40J
substitute into K1 + Ue1 = K2 + Ue2
Ue2 = K1 + Ue1 - K2
= 10 +100 - 40
Ue2 = 70J