Download F = qvB sin θ

Worksheet Physics Ideas to Implementation (2)
Name:______________
DOT POINT
 explain that cathode ray tubes allowed the manipulation of a stream of charged particles
 identify that moving charged particles in a magnetic field experience a force
 identify that charged plates produce an electric field
 describe quantitatively the force acting on a charge moving through a magnetic field
F  qvB sin 
Formulae Sheet/ Data sheet – at end of your exam- you will need in this sheet.
Q 1: Derive a formula F on an electron e = qe, between plates separated by d, and with a voltage V
𝐹 = 𝑉𝑞/𝑑
Q2 : Derive a formula r radius of curvature of an electron, velocity v and field B Tesla.
𝑟 = 𝑚𝑣/𝑞𝐵𝑠𝑖𝑛𝜃
Q3: Derive a formula v in terms B and E fields set to counter act each other
𝑣 = 𝐸/𝐵
Q4: Arrange formula in Q2 and Q3 to get q/m
𝑞
𝐸
= 2
𝑚 𝐵 𝑟
Q5 What three quantities did Thompson measure to find the charge (q) to mass (m) ratio.
From 2008
Worksheet Physics Ideas to Implementation (2)
Name:______________
From Question 3 what two physical constants do you have to look up in the data sheet to answer this?
9.1E-31x8E6/1.6E-19/2.1E-2
From 2007
Use an equation linking E, V and d
From 2006
Worksheet Physics Ideas to Implementation (2)
Name:______________
Remember the right hand slap rule and the current or charge direction on the thumb, and the direction of the
field fingers.
From 2005
Worksheet Physics Ideas to Implementation (2)
Name:______________
Worksheet Physics Ideas to Implementation (2)
Name:______________
Hint Write Formula for moment p, Centripetal Force, and F magnetic to get p= qBr
Find p of photon and divide by velocity
Use relativity