Genitive in many cases has "possessive" meaning, answering the question "whose", "of what", "of whom". It will be the same for all the measures like:
Cake of what size? Cake of what length? Cake of what taste?
Ты хочешь торт какого размера/какой длины/какого вкуса?
Also, it's unusual to hear "Ты хочешь торт какого размера?", as too much emphasys is placed on the "of what size?" in this sentence, the meaning is close to that of "What size is it that you want a cake of?". It is more common to hear people saying "Торт какого размера ты хочешь?"
Other possible natural order of words is "Какого размера торт ты хочешь?". As for the original oreder, it's not totally wrong. For instance, I can imagine the following conversation: - Я хочу торт! - Ты хочешь торт какого размера?
In that conversation the second person adds bit of irony by parroting the first person.
Original sentence: "Ты хочешь торт какого размера?" - "режет ухо". It should be two questions: "Ты хочешь торт? Какого размера?", or as you put it: "Какого размера торт ты хочешь?"
Original form reminds me a joke from one popular Russian TV show: "В каком году жил писатель который что сказал?"
There's a whole field of syntax devoted to questions of "superiority effects," which show up when you're trying to question two pieces in what sentence (like the year and what the writer said, in your example). The general consensus is that they always sound pretty weird, but some variants sound weirder than others. For example, "who said what?" is better than "what did who say?" Ivan Sag has written a bit about this, but usually in English, rather than Russian.
please, use English in this community and please, remember that russian grammar for foreigners is "slightly" different as one for Russian native speakers if you are not familiar with the first one, please, do not correct me
I am not sure if I am entirely correct trying to generalise on the spot, but at a first glance it seems a general rule to use Genitive for a phrase consisting of a noun+adjective describing another noun. The noun described might be used in any Case.
And, of course, luckily for us natives it's not a rule to remember, it just comes naturally.
no subject
Date: 2011-11-01 06:17 pm (UTC)Cake of what size? Cake of what length? Cake of what taste?
Ты хочешь торт какого размера/какой длины/какого вкуса?
Also, it's unusual to hear "Ты хочешь торт какого размера?", as too much emphasys is placed on the "of what size?" in this sentence, the meaning is close to that of "What size is it that you want a cake of?". It is more common to hear people saying "Торт какого размера ты хочешь?"
no subject
Date: 2011-11-01 06:36 pm (UTC)- Я хочу торт!
- Ты хочешь торт какого размера?
In that conversation the second person adds bit of irony by parroting the first person.
no subject
Date: 2011-11-01 11:35 pm (UTC)Original form reminds me a joke from one popular Russian TV show: "В каком году жил писатель который что сказал?"
no subject
Date: 2011-11-02 03:01 pm (UTC)no subject
Date: 2011-11-01 08:02 pm (UTC)It's just a personal style of speaking. Sounds colloquial.
no subject
Date: 2011-11-01 08:02 pm (UTC)no subject
Date: 2011-11-01 10:26 pm (UTC)no subject
Date: 2011-11-01 06:51 pm (UTC)Gen is usually used for size and color
У тебя синие глаза = у меня глаза синего цвета
у тебя большие кроссовки = у тебя кроссовки большого размера
no subject
Date: 2011-11-01 10:35 pm (UTC)no subject
Date: 2011-11-02 08:50 am (UTC)and please, remember that russian grammar for foreigners is "slightly" different as one for Russian native speakers
if you are not familiar with the first one, please, do not correct me
no subject
Date: 2011-11-01 07:32 pm (UTC)no subject
Date: 2011-11-01 07:42 pm (UTC)no subject
Date: 2011-11-01 08:40 pm (UTC)Какой размер у торта?
no subject
Date: 2011-11-01 08:43 pm (UTC)no subject
Date: 2011-11-01 08:59 pm (UTC)So, I meant a word "торт".
no subject
Date: 2011-11-01 09:06 pm (UTC)no subject
Date: 2011-11-01 10:46 pm (UTC)no subject
Date: 2011-11-01 10:33 pm (UTC)Хотеть-после него винительный падеж.
Я хочу (кого?, что?) торт.
"Какого размера" согласовывается со словом "торт". Поэтому род. падеж.
По немецки это бы было:
Ich will Torte welchER Größe?
no subject
Date: 2011-11-01 10:49 pm (UTC)Я подошел к торту большого размера.
Я бросил в него тортом большого размера.
Я разговаривал о торте большого размера.
The case of размера does NOT depend on the case of торт. See the examples above.
no subject
Date: 2011-11-01 11:13 pm (UTC)no subject
Date: 2011-11-01 11:14 pm (UTC)This is exactly what the original poster asked. Why, if размер is directed by торт, it should be in genitive?
no subject
Date: 2011-11-01 10:55 pm (UTC)And, of course, luckily for us natives it's not a rule to remember, it just comes naturally.