What will happen to the elastic property of Gold when Potassium is added to gold?
A.
The elastic property of gold decreases
B.
The elastic property of gold remains unaltered
C.
The elastic property of gold increases
D.
Gold loses its elastic property
Answer: Option C
Explanation:
The addition of impurities causes variation in the elastic property of materials. Potassium when added to gold increases its elasticity thereby making it easy to be electroplated.
A copper wire of length 3m and 1mm diameter is subjected to a tension of 5N. Calculate the elongation produced, if the young’s modulus of copper is 120GPa.
The modulus of rigidity and Poisson’s ratio of the wire are 2.87 × 1010 N/m2 and 0.379 respectively. What is the value of young’s modulus of the material of the wire.
What is the effect of annealing on elasticity of materials?
A.
Increases the elasticity
B.
Decreases the elasticity
C.
Has no effect on elasticity
D.
Distorts the material
Answer: Option B
Explanation:
Annealing is the process of heating a material and then gradually cooling it. While annealing, constituent crystals are uniformly oriented and form larger crystal grains, which results in a decrease in their elastic properties.