Since , resistances are joined in parallel , potential difference across either of R₁ or R₂ will be same , and it will be equal to emf of the cell provided no internal resistance exists in the cell.
Since potential difference across R₁ is equal to emf and resistance is R₁ , current through it too will be same as that in the previous case.
We are assuming that the floor (field) is completely horizontal since there's no information about that in the statement. We are going to use the following formula:
The contribution of the wavelets lying on the back of the wave front is zero because of something known as the Obliquity Factor. It is assumed that the amplitude of the secondary wavelets is not independent of the direction of propagation, Sources: byju's.com
