Concept: Canal rays (positive rays) consist of massive, positively charged ions. Because they possess significant mass and velocity, they carry kinetic energy and momentum.
Formula: $$ p = mv $$
Solution: - If a small paddle wheel is placed in the path of canal rays inside a discharge tube, the rays will strike the wheel.
- Because canal rays are relatively heavy material particles (entire atoms missing an electron), they transfer their momentum to the wheel.
- This momentum transfer causes the wheel to physically rotate, proving that canal rays can and do cause mechanical motion.
- Therefore, the statement "Do not cause mechanical motion" is strictly false.
Why other options are incorrect: Canal rays from Hydrogen gas specifically match the mass in Option A and the charge-to-mass ratio in Option B. Because they are charged particles, they do deflect in electric and magnetic fields (Option C is true).
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