PRACTICE PAPER - 1

How does the action of a concave lens differ from that of a convex lens on a parallel beam of light incident on them? Draw diagrams to illustrate your answer.

Three cells each of emf $E$ and internal resistance $r$ are joined in parallel to a resistance $R$. Find the expression for the current across the resistance.   

For the combination of resistors shown in the figure below, calculate the equivalent resistances between $\mathrm{A}$ and $\mathrm{B}$.

For the combination of resistors shown in the figure below, calculate the equivalent resistances between $\mathrm{A}$ and $\mathrm{B}$.

What is a solenoid? How will you find the polarity at the ends of solenoid, without using magnetic needle?

Draw a neat and labelled diagram of a D.C motor and explain its construction.   

Complete the diagram showing the path of $\alpha$, $\beta$ and $\gamma$ radiations in an electric field. 

Name the radiation which have the lowest penetrating power.