Question

Observation:
In the alpha particle scattering experiment, it was observed that few of the alpha particles were deflected at angles greater than ${90}^{\circ }$

Inference:
Only a large proportion of the entire charge should be concentrated at the center of the atom and not the mass.

• A. Both observation and its inference are correct
• B. Observation is wrong and its inference is incorrect too.
• C. Observation is correct but inference is wrong
• D. Both observation and inference are correct but the given statement is not a direct inference of the given observation.

Answer 1

The correct option is C Observation is correct but inference is wrong

If alpha particle is getting deflected at angles larger than ${90}^{\circ }$ then both- a large proportion of entire charge and mass should be concentrated at the center of the atom, because if there was only charge and very less mass then the nucleus will be knocked out by the high energy alpha particles.
It's like throwing a large magnet with high velocity towards a small stationary magnet kept on a table.
Even though these magnets will repel each other but still the large magnet has a higher momentum and will push the small magnet out from the table.

But here if the situation was reversed. If the magnet on the table was more massive and the one thrown at it was small, then if they hit head on then the smaller magnet might be repelled back without disturbing the magnet on the table by a lot.