a spring board diver intending to do a somersault brings her knees and arms closer to her body during the dive what effect does this have

Question

***[isuru]*** · Answer

do u know about the rotational inertia ?

anonymous · Answer

ok thats the thing were i get confused no could you explain me that please

***[isuru]*** · Answer

ok ... the rotational inertia is the tendency of an rotating object to keep rotating unless a torques applies on it ... i guess u know about the toque

anonymous · Answer

ok so the moment of inertia would decrease?

anonymous · Answer

ok but the question doesnt tell me the mass or nothing

***[isuru]*** · Answer

srry ... i made a mistake earlier... something should  be corrected

***[isuru]*** · Answer

if the rotational inertia of a object is low.. then it will like to rotate .. if the rotational inertia of a object is high it will be difficult to rotate it

***[isuru]*** · Answer

the rotational inertia basically depends on 2 things... 
           1. mass of the object..
           2. and the distance from the axis of rotation to the center of mass

anonymous · Answer

ok these are the answer choices a. it makes her fall more slowly b. it decreases her moment of inertia c. it decreases he angular velocity d. it increases her angular momentum

anonymous · Answer

thats why im confused because it doesnt give me mass or the distance

***[isuru]*** · Answer

and the trick to this question lies in the position of the man... and remember the rotational inertia is directly proportional to the above mention 2 factors

***[isuru]*** · Answer

if the mass increase ... rotational inertia increase
if the distance increase ... rotational inertia too increase

***[isuru]*** · Answer

basically he need to perform acrobatics when he jumps from the board

***[isuru]*** · Answer

which mean he wants to rotate his body around a axis ...

anonymous · Answer

so would it be c?

anonymous · Answer

wait no it would be b right

***[isuru]*** · Answer

to rotate his body without much effort he need to decrease his rotational innertia

***[isuru]*** · Answer

since he cant decrease his mass he can decrease his rotational inertia by decreasing the distance

anonymous · Answer

can you tell me it the answer is B.?

***[isuru]*** · Answer

yep!

anonymous · Answer

ok thank you!!!

***[isuru]*** · Answer

u r welcome..  :)

anonymous · Answer

thank you so much for taking your time i really didnt get it but now  i do thanks!