Choose the graph that best describes the variation of dielectric constant (\( \epsilon_r \)) with temperature (\( T \)) in a ferroelectric material.
(T\(_C\) is the Curie temperature)
Choose the graph that best describes the variation of dielectric constant (\( \epsilon_r \)) with temperature (\( T \)) in a ferroelectric material.
(T\(_C\) is the Curie temperature)
Show Hint
- \( \epsilon_r \) increases sharply and then decreases near \( T_C \).
- \( \epsilon_r \) jumps discontinuously at \( T_C \).
- \( \epsilon_r \) increases continuously after \( T_C \).
- \( \epsilon_r \) decreases sharply as \( T \) increases.
The Correct Option is A
Solution and Explanation
Step 1: As the temperature approaches \( T_C \) from below, \( \epsilon_r \) increases sharply, reaching a maximum value at \( T_C \).
Step 2: Above \( T_C \), the dielectric constant starts decreasing rapidly, indicating the loss of ferroelectric properties and transition to a paraelectric state.
This behavior is best represented by graph (A).
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