Question

Figure shows tracks of three charged particles in a uniform electrostatic field. Given the signs of the three charges. Which particle has the highest charge to mass ratio.

Answer 1

Look carefully at the path which the 3 particles have followed, before entering the field and after leaving it.

You can see that particle 3 has deviated the most.

By coulomb's law, the particle with highest charge will experience the greatest force, while passing through an electric filed.

As per Newton's laws of motion, lighter particle will deviate the most because it will undergo greater acceleration.

Thus we can say that $deviation$ proportional to $\frac{charge}{mass}$

Hence the particle with the highest $\frac{charge}{mass}$ ratio will undergo maximum deviation.

Hence $3$ has the maximum $\frac{charge}{mass}$ ratio.