Electrons having a velocity `vecv` of `2xx10^(6)ms^(-1)` pass undeviated through a uniform electric field `vecE` of intensity `5xx10^(4)Vm^(-1)` and a uniform magnetic field `vecB`.
(i) Find the magnitude of magnetic flux density B of the magnetic field.
(ii) What is the direction of `vecB`, if `vecv` is towards right and `vecE` is vertically downwards in the plane of this paper ?

Explanation

To solve the problem, we will follow these steps:

### Step 1: Write down the given values
- Velocity of electrons, \( v = 2 \times 10^6 \, \text{m/s} \)
- Electric field intensity, \( E = 5 \times 10^4 \, \text{V/m} \)

### Step 2: Use the formula for the relationship between electric field, magnetic field, and velocity
When electrons pass undeviated through both electric and magnetic fields, the electric force is balanced by the magnetic force. The relationship can be expressed as:
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