Calculate the magnitude of magnetic field at a distance of (4.000x10^0) mm from a long straight wire with a current of (3.5x10^2) amps flowing in it. Give your answer in Tesla, to 2 sf.

Calculate the radius of the orbit of a proton moving at (2.23x10^6) m/s in a magnetic field (3.5x10^-1) T where v and B are perpendicular. Give your answer in centimetres to 2 s.f.

The beam of electrons goes undeflected when passing through crossed electric and magnetic fields of magnitude (1.23x10^4) V/m and (4.2x10^-3)T, respectively. What is the radius of the electron orbit, in mm, if the electric field is turned off? Give your answer to 2 sf.

The magnetic field in a cyclotron is (2.7x10^-1) T. What must the minimum radius of the dees be in metres, if a proton beam is to be produced with a maximum speed of (6.580x10^7)m/s? Give answer to 2 s.f.

What is the velocity of a beam of electrons that go undeflected when passing through crossed electric and magnetic fields of magnitude (2.220x10^4) V/m and (2.40x10^-3) T, respectively? Give your answer to 3 sf.

Protons move in a circle of radius (4.500x10^0) cm in a (5.78x10^-1) T magnetic field. What value of electric field could make their paths straight? Give your answer to 3 sf.

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