In a model of birth, the strength of the contractions starts at c units…
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
In a model of birth, the strength of the contractions starts at units. Each round multiplies it by a gain . Birth needs a strength of at least units.
- How many rounds are needed if and ?
- How many rounds are needed if and ?
- How many rounds are needed if and ?
Need a reminder? The key ideaShow
Parturition: the fully developed foetus and the placenta send signals, the uterus contracts mildly (the foetal ejection reflex), the pituitary releases oxytocin, the contractions become stronger, and more oxytocin is released. This is positive feedback. In a model with a first strength and a gain , the strength after rounds is . The first milk is the colostrum, rich in antibodies. Prolactin makes milk, and oxytocin ejects it.
The worked solution
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Given. Target: units. Strength after rounds: .
Plan. Solve for the smallest whole number .
Step 1. (a) . The smallest whole number is .
Step 2. (b) . The smallest whole number is .
Step 3. (c) . The smallest whole number is .
Answer: rounds; rounds; rounds.
Check. A larger gain gives fewer rounds, and a stronger start gives fewer rounds.
Discussion (0)
Log in to join the discussion.
Loading…