The magnetic field inside a current-carrying toroidal solenoid is $0.2 \ mT$. What is the magnetic field inside the toroid if the current is tripled (in $mT$)?

$A$ long solenoid of $50\, cm$ length having $100$ turns carries a current of $2.5\, A$. The magnetic field at the centre of the solenoid is $...... \times 10^{-5}\, T$. $(\mu_{0} = 4\pi \times 10^{-7}\, T\, m\, A^{-1})$

In a current-carrying long solenoid,the magnetic field produced does not depend upon:

$A$ thin hollow copper pipe carries a direct current. Which of the following statements is incorrect?

$A$ solenoid is $1 \ m$ long and $4 \ cm$ in diameter. It has five layers of windings of $1000$ turns each and carries a current of $7 \ A$. The magnetic field at the centre of the solenoid is

$A$ current of $5 \ A$ flows through a toroid having a core of mean radius $20 \ cm$. If $4000$ turns of the conducting wire are wound on the core,then the magnetic field inside the core of the toroid is [permeability of free space $= 4 \pi \times 10^{-7} \ T \cdot m/A$]