Embibe Experts Solutions for Chapter: Electromagnetic Induction, Exercise 1: chhattisgarh board-2019

What is coefficient of self-inductance? An iron-cored solenoid has self-inductance of $2.8 \mathrm{H}$. When the core is removed, the self inductance becomes $2 \mathrm{mH}$. What is the relative permeability of the core used?

Vandana was a student of Class 12th Science. She went to visit a science centre with her friends. There, she saw a magnet oscillating through a string. She observed that oscillation stops when a metal plate is kept under the oscillating magnet. She could not understand the reason. She discussed with her friends that oscillation will continue or stop when the magnet is kept under the oscillating metal plate. The next day, they went to their science teacher and became happy to know the reason for the phenomenon. 

Why oscillation stops when a metal plate is kept under the oscillating magnet? Give suitable reason.

Vandana was a student of Class 12th Science. She went to visit a science centre with her friends. There, she saw a magnet oscillating through a string. She observed that oscillation stops when a metal plate is kept under the oscillating magnet. She could not understand the reason. She discussed with her friends that oscillation will continue or stop when the magnet is kept under the oscillating metal plate. The next day, they went to their science teacher and became happy to know the reason for the phenomenon. 

Write two properties of current produced in the metal plate. How we can reduce this current? Write.

Vandana was a student of Class 12th Science. She went to visit a science centre with her friends. There, she saw a magnet oscillating through a string. She observed that oscillation stops when a metal plate is kept under the oscillating magnet. She could not understand the reason. She discussed with her friends that oscillation will continue or stop when the magnet is kept under the oscillating metal plate. The next day, they went to their science teacher and became happy to know the reason for the phenomenon. 

Write two values each shown by the teacher and Vandana. 

The magnetic flux linked with a closed-loop is ${\varphi }_B=6t^2+7t+1$, where ${\varphi }_B$, in milli-Weber and $t$ in second. What will be the induced e.m.f. after $t=2$  seconds? 

Ajay and his friends went for a walk. There they saw a metallic chain attached to a truck touching the ground. It was also written on the truck, “beware highly inflammable". Ajay explained to his friends that during motion of truck, magnetic lines of the earth are cut by its axle and due to this some e.m.f. will be induced across its ends. This induced charge is discharging to the earth through this metallic chain and explosive materials are safe. Answer the following questions on the basis of the above paragraph : 

When does an induced e.m.f produce? 

Ajay and his friends went for a walk. There they saw a metallic chain attached to a truck touching the ground. It was also written on the truck, “beware highly inflammable". Ajay explained to his friends that during motion of truck, magnetic lines of the earth are cut by its axle and due to this some e.m.f. will be induced across its ends. This induced charge is discharging to the earth through this metallic chain and explosive materials are safe. 

Answer the following questions on the basis of the above paragraph : Name and state the law which gives direction of induced current. 
 

Ajay and his friends went for a walk. There they saw a metallic chain attached to a truck touching the ground. It was also written on the truck, “beware highly inflammable". Ajay explained to his friends that during motion of truck, magnetic lines of the earth are cut by its axle and due to this some e.m.f. will be induced across its ends. This induced charge is discharging to the earth through this metallic chain and explosive materials are safe. 

Answer the following questions on the basis of the above paragraph : Write the values displayed by Ajay (any two).