Under what conditins permanent electromagnet is obtianed if a current carrying solenoid is used? Support your answer with the help of a labelled circuit diagram.

What do you understand by the development of an embryo. Support your answer with the help of suitable diagrams.

Concentrated sulphuric acid is added followed by heating to each of the following test tubes labelled (i) to (v). Identify in which of the above test tube the following change will be observed. Support your answer with the help of a chemical equation. Formation of black substance.

Concentrated sulphuric acid is added followed by heating to each of the following test tubes labelled (i) to (v). Identify in which of the above test tube the following change will be observed. Support your answer with the help of a chemical equation. Disappearance of yellow powder along with evolution of colourless gas.

Concentrated sulphuric acid is added followed by heating to each of the following test tubes labelled (i) to (v). Identify in which of the above test tube the following change will be observed. Support your answer with the help of a chemical equation. Evolution of brown gas.

Concentrated sulphuric acid is added followed by heating to each of the following test tubes labelled (i) to (v). Identify in which of the above test tube the following change will be observed. Support your answer with the help of a chemical equation. Evolution of brown gas.

Concentrated sulphuric acid is added followed by heating to each of the following test tubes labelled (i) to (v). Identify in which of the above test tube the following change will be observed. Support your answer with the help of a chemical equation. Evolution of colourless gas.

Concentrated sulphuric acid is added followed by heating to each of the following test tubes labelled (i) to (v). Identify in which of the above test tube the following change will be observed. Support your answer with the help of a chemical equation. Formation of black substance.

Using Ampere's circuital law, obtain an expression for the magnetic field along the axis of a current carrying solenoid of lenth l and having N number of turns.

Long Answer Questions Five mark Each QUESTIONS FROM STATE BOARD EXAMINATIONS : Explain megasporogenesis till the formation of embryo sac. Support your answer with a labelled diagram.