How is an ammeter connected in a circuit?

State $Ohm's$ law. Write the mathematical representation of $Ohm's$ law. Use this relationship to define $1\, ohm.$ List two disadvantages of connecting different electrical appliances in series.

If three resistors of $5 \Omega$,$10 \Omega$,and $15 \Omega$ are connected in series,the equivalent resistance $R$ is equal to ........ (in $Omega$)

In an experimental set-up as shown below,a piece of silver was placed touching points $A$ and $B$. Next time it was replaced by a piece of wood. In which case did the bulb glow? Give reason to justify the observation.

The electric current flowing through any conductor is directly proportional to the electric potential difference across the conductor. Which law is this?

Why is heat produced when a current is passed through a conductor?