An $\alpha$-particle and a $\beta$-particle possess the same kinetic energy. Why does the $\alpha$-particle produce a greater ionising effect than the $\beta$-particle when it travels through air?
- AThe $\alpha$-particle has a larger charge and a larger velocity so is closer to an air particle for a shorter time.
- BThe $\alpha$-particle has a larger charge and a smaller velocity so is closer to an air particle for a longer time.
- CThe $\alpha$-particle has a smaller charge and a larger velocity so is closer to an air particle for a shorter time.
- DThe $\alpha$-particle has a smaller charge and a smaller velocity so is closer to an air particle for a longer time.