1-Rupee and Us Dollar relation.
The value of Indian Rupee in US dollars is decided on the basis of amount of goods/services that costs in both the countries. For example, if one dollar is equal to fifty rupees, then it simply means that the good/services which costs 1 US dollar in United States would cost Rs. 50 in India.
2-Meaning of dropping of value of Rupee against US Dollar.
If the value of a currency increases against another currency, it is called currency appreciation and drop in the value of a currency against the other is called currency depreciation.
Drop in the value of Rupee against dollar means if earlier u can purchase 1 Dollar in 50 rupees, now 1 dollar will cost u more than that, say Rs 51 , which means that dollars has strengthened.
This depends on the value of capital inflows in the country.
That's all there in my head at this current moment.