Answer:
a
The largest diameter is
![d = 0.523 \ m](https://img.qammunity.org/2021/formulas/physics/high-school/24jjo4oelbdvis97n0476cxtpt2tc7qhmm.png)
b
The number of revolution is
![n = 2.132 *10^(4)](https://img.qammunity.org/2021/formulas/physics/high-school/x7m27cl3u5582uaxzowc38y4tzzboesz2k.png)
Step-by-step explanation:
From the question we are told that
The kinetic energy of the electron is
![K = 6.5 MeV = 6.5 *10^6 * 1.60 *10^(-19) = 1.04 *10^(-12) \ J](https://img.qammunity.org/2021/formulas/physics/high-school/srzd1nt2bfgjj1tzne3l1hk504amotq1r2.png)
The magnetic field is
![B = 1.4 \ T](https://img.qammunity.org/2021/formulas/physics/college/oep5hni88se0gxxn49k39tskt82lcise5n.png)
The time is
![t = 1 ms = 1*0^(-3) \ s](https://img.qammunity.org/2021/formulas/physics/high-school/vchtb2lio4zeuum61gqsyg4oam614nfdej.png)
Generally the kinetic energy of the proton is mathematically represented as
![KE = (1)/(2) * m * v^2](https://img.qammunity.org/2021/formulas/physics/high-school/ix487ozsosizvnf48ehlnzbpg9azb4htm8.png)
Here m is the mass of the proton with a value
![m = 1.672 *10^(-27) \ kg](https://img.qammunity.org/2021/formulas/physics/high-school/iu2qocvlltfujys5ydkmmnio1u1yfc557v.png)
=>
![v = \sqrt{ (2 * K )/( m) }](https://img.qammunity.org/2021/formulas/physics/high-school/3cfy7h2xzudp6bml2jdwyshi96drmgaec9.png)
=>
![v = \sqrt{ (2 * 1.04 *10^(-12) )/( 1.672 *10^(-27)) }](https://img.qammunity.org/2021/formulas/physics/high-school/buxzxrncqh0p87cr2vaq6w4ed7xbrrr9s6.png)
=>
![v = 3.5271 * 10^(7) \ m/s](https://img.qammunity.org/2021/formulas/physics/high-school/7jja6lctca9codkyrkkoa2b5846hd8oyw0.png)
Generally the radius of the largest orbit is mathematically represented as
![r = ( m * v)/( B * e)](https://img.qammunity.org/2021/formulas/physics/high-school/8cnhwsxdsfcl7fd5f03x4mskl0760cm0ic.png)
Here e is the charge on a proton with the value
![e = 1.60 *10^(-19) \ C](https://img.qammunity.org/2021/formulas/physics/college/kjub41ykbxwelmn40jv6z3wgja19omhssf.png)
![r = ( 1.672 *10^(-27) * 3.5271 * 10^(7) )/( 1.4 * 1.60 *10^(-19) )](https://img.qammunity.org/2021/formulas/physics/high-school/mwr83zpyxpq5zomxsiqck1j70ri8nnxzkc.png)
=>
Generally the diameter is
![d = 2 * r](https://img.qammunity.org/2021/formulas/physics/college/ylbvlb9u1g0c5p6n3ejott19ko9zq018ok.png)
=>
![d = 2 * 0.261](https://img.qammunity.org/2021/formulas/physics/high-school/igo8ngpncv8x04l6yrm7drvhu7kqctfifg.png)
=>
![d = 0.523 \ m](https://img.qammunity.org/2021/formulas/physics/high-school/24jjo4oelbdvis97n0476cxtpt2tc7qhmm.png)
Gnerally the period of revolution round the orbit is mathematically represented as
![T = (2 \pi * m )/(B * e)](https://img.qammunity.org/2021/formulas/physics/high-school/hm567kad8ccx0ql8b8aepl8qc1iecfcuuo.png)
=>
![T = (2 * 3.142 * 1.672 *10^(-27) )/(1.4 * 1.60 *10^(-19))](https://img.qammunity.org/2021/formulas/physics/high-school/kejx2ks6cz9rtbvjwb6p618k1h65lzrj3d.png)
=>
![T = 4.691 *10^(-8) \ s](https://img.qammunity.org/2021/formulas/physics/high-school/hl5p10qtazecll43yqb2460fric7wcqfd8.png)
Generally the number of revolution is mathematically represented as
![n = (t)/(T)](https://img.qammunity.org/2021/formulas/mathematics/college/qcy63ljdouniqbo2206bybua1w6viy9azg.png)
![n = (1*10^(-3))/(4.691 *10^(-8) )](https://img.qammunity.org/2021/formulas/physics/high-school/uws3b9lef54phzrwvkam3p339hnyzwy0cg.png)
![n = 2.132 *10^(4)](https://img.qammunity.org/2021/formulas/physics/high-school/x7m27cl3u5582uaxzowc38y4tzzboesz2k.png)