Unit 2: Particles

Question 1

What are charges effected by

Answer 1

Magnets

Question 2

What was Thomson’s experiment an what was the conclusion

Answer 2

Pass electric current through a cloud of gas- gas made up of atoms and are neutral (magnets shouldn’t affect them) and the gas starts to glow. Phosperestant background

The current causes excitations/deexcitations in the gas, giving off visible light.
The glowing beam could be deflected by a magnet.

Conclusion- must have charge inside the atom -ve electrons in dilute positive region

Question 3

What was Rutherford’s experiment and what was the conclusion

Answer 3

Alpha particle fired at gold foil
A particles are +ve but shouldn’t affect the atom as +ve region is so dilute
A particals were deflected and even bounced back most of the atoms was empty space as most of the atoms went straight through.

Conclusion- must have a concentrated +ve region. it must be dense/massive as A particles are big and they bounced back

Question 4

RM RC of electrons protons and neutroms

EC of quarks

Answer 4

Electrons RM 0.0005 RC-1
Protons RM1 RC1
Neutrons RM1 RC0

U- 2/3
D- (-1/3)

Question 5

How does E=MC^2 apply to atoms

Answer 5

the mass of individual protons and neutrons are larger than the mass combined as some mass is converted to energy to keep them together