A beam of well collimated cathode rays travelling with a speed of $5 \times {10^6}\,m{s^{ - 1}}$ enter a region of mutually perpendicular electric and magnetic fields and emerge undeviated from this region. If $| B |=0.02\; T$, the magnitude of the electric field is
Medium
Download our app for free and get started
(a) Using $eE = evB$
$ \Rightarrow E = vB = 5 \times {10^6} \times 0.02 = {10^5}\,V{m^{ - 1}}$
Download our appand get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
Similar Questions
- 1A current loop $ABCD$ is held fixed on the plane of the paper as shown in the figure. The arcs $ BC$ (radius $= b$) and $DA $ (radius $= a$) of the loop are joined by two straight wires $AB $ and $CD$. A steady current $I$ is flowing in the loop. Angle made by $AB$ and $CD$ at the origin $O$ is $30^o $. Another straight thin wire with steady current $I_1$ flowing out of the plane of the paper is kept at the origin.View Solution
Due to the presence of the current $I_1$ at the origin
- 2Two identical circular wires of radius $20\,cm$ and carrying current $\sqrt{2}\,A$ are placed in perpendicular planes as shown in figure. The net magnetic field at the centre of the circular wire is $.............\times 10^{-8}\,T$. (Take $\pi=3.14$ )View Solution
- 3The earth’s magnetic field at a given point is $0.5 \times {10^{ - 5}}\,Wb{\rm{ - }}{m^{ - 2}}$. This field is to be annulled by magnetic induction at the center of a circular conducting loop of radius $5.0\,cm$. The current required to be flown in the loop is nearly......$A$View Solution
- 4Two parallel wires of length $9\, m$ each are separated by a distance $0.15\, m$. If they carry equal currents in the same direction and exerts a total force of $30 \times 10^{-7} \,N$ on each other, then the value of current must be........$amp$View Solution
- 5A galvanometer has a resistance of $25\, ohm$ and a maximum of $0.01\, A$ current can be passed through it. In order to change it into an ammeter of range $10\, A$, the shunt resistance required isView Solution
- 6View SolutionThe ratio of the magnetic field at the cpentre of a current carrying circular wire and the magnetic field at the centre of a square coil made from the same length of wire will be
- 7Current $I$ is flowing in conductor shaped as shown in the figure. The radius of the curved part is $r$ and the length of straight portion is very large. The value of the magnetic field at the centre $O$ will beView Solution
- 8View SolutionTwo parallel wires are carrying electric currents of equal magnitude and in the same direction. They exert
- 9Three long current carrying wires $P, Q$ and $R$ placed perpendicular to plane of the paper. Magnetic force per unit length on wire $'R'$ isView Solution
- 10A helium nucleus makes a full rotation in a circle of radius $0.8$ metre in two seconds. The value of the magnetic field $B$ at the centre of the circle will beView Solution