Before targeting $100 a day in Google Adsense it is better to plan for $1 a day means $30 a month.
To earn $1 a day from Google adsense is good start for beginners.
Lets Discuss how much traffic , page views, cpc(cost per click) and CTR do you need to earn $1 a day .
With average of 3% of CTR and CPC of $ 0.05 you need 100 page views to get 3 clicks and u will earn $0.15 for each click. but your target is to achieve $1 a day . It means you need 667 page view and 20 clicks to earn $1 a day.
Dont worry about 20 clicks. when you get 667 page view you will automatically get approximately 20 click .
So now what you have to do is to optimize you blog to get 667 page views.
and you can do this by search engine optimization and by increasing your blog exposure.
Remember that earnings money from Google Adsense takes time and requires patience.
dont worry about earnings. work on your website and its content .
if your dedicated toward towards your target you will definitely get it.