you can study for a half hour
it doesn't take a half hour break to recharge your batteries
for most people about five minutes
and this is where you go away do something fun
for five minutes
call a friend talk to a child talk to a parent a roommate
enjoy some music
do something you enjoy and actually say this is my treat for having studied for thirty minutes effectively
go back and here's what happens
your efficiency is nearly one hundred percent
study a half hour take a break study a half hour study
the head she'd done now
over the course of six hours
she would have got about five and half hours of serious study
and about a half hour of total break time