You are Here: Home >< GCSEs

Announcements Posted on
Last day to win £100 of Amazon vouchers - don't miss out! Take our quick survey to enter 24-10-2016
1. Hey, I'm confused as to how a small surface area compared to volume (or a round shape) helps reduce heat loss, and a large surface area compared to volume helps lose heat. Can someone explain both of these please? (Especially the volume part).

Also, I read that "In rainforests, plants have shiny surfaces and pointed tips for rain", can someone make sense of this please?
2. (Original post by Perfection Ace)
Hey, I'm confused as to how a small surface area compared to volume (or a round shape) helps reduce heat loss, and a large surface area compared to volume helps lose heat. Can someone explain both of these please? (Especially the volume part).

Also, I read that "In rainforests, plants have shiny surfaces and pointed tips for rain", can someone make sense of this please?
You can think of it similarly to diffusion in that a large surface area means that something, in this case heat, can be transferred much more easily over a large surface area. This is because there is more space for heat to be lost from, the opposite is true for a small S.A. to volume ratio.
3. (Original post by Perfection Ace)
Hey, I'm confused as to how a small surface area compared to volume (or a round shape) helps reduce heat loss, and a large surface area compared to volume helps lose heat. Can someone explain both of these please? (Especially the volume part).

Also, I read that "In rainforests, plants have shiny surfaces and pointed tips for rain", can someone make sense of this please?
Hiya
I never understood the whole concept of 'surface area:volume ratio' until my teacher explained it using a pile of text books; if you take a pile of text books and stack them on top of each other, then take half off, you can see that while the volume halves, the surface area decreases far less dramatically because it is only the surface area of the sides of the books that decreases.

I'm not sure if that makes sense, I'm a visual learner so I'd say it's best to physically get the books and have a look at it working for yourself if you think that would help you. In the case of animals, a small surface area:volume ratio reduces heat loss because there's less skin (area) exposed around the animal, so a smaller area of skin over which heat can be lost from via radiation. Conversely, a large surface area:volume ratio increases heat loss because there's more skin (area) exposed around the animal, in relation to its size, so there's a larger amount of skin (surface area) by which heat can be lost via radiation.

For example: the elephant. If an elephant had no flaps of skin, it would have the same volume because it would be the same size, but a smaller surface area because there would be less skin around it. Therefore, less heat would be lost via radiation if the elephant had no flaps of skin because, for the same size elephant, less heat is lost from the skin through radiation.

I hope that's helpful, if it's not then I can try and re-word it or find a visualisation. It all links to the amount of heat that an be lost by radiation in animals.

As for the plants in rainforests; I am aware that leaves in rainforests are often thick and shiny to protect from extreme sunlight, however I'm unsure with regards to rain. Leaves coated in grease take in far less water, so I assume it would work in a similar way and attempt to protect the leaf from absorbing too much water. Likewise, I think the pointed tips are designed so that water drips off the leaf quickly after rainfall, which might aid in allowing more sunlight to be absorbed, as that is more in demand that rainfall in the rainforest.

However that is mostly speculation, so don't take my word for it! Hope that helps
4. It links to P1; you should know that heat is emitted from the surface of an object. A high surface area to volume ratio gives an animal more surface area to emit heat from, letting more heat be emitted and cooling it down. A high volume to surface area ratio will conserve heat due to the smaller surface for heat to be emitted from.
5. (Original post by halfblackdragon)
You can think of it similarly to diffusion in that a large surface area means that something, in this case heat, can be transferred much more easily over a large surface area. This is because there is more space for heat to be lost from, the opposite is true for a small S.A. to volume ratio.
(Original post by CaptErin)
Hiya
I never understood the whole concept of 'surface area:volume ratio' until my teacher explained it using a pile of text books; if you take a pile of text books and stack them on top of each other, then take half off, you can see that while the volume halves, the surface area decreases far less dramatically because it is only the surface area of the sides of the books that decreases.

I'm not sure if that makes sense, I'm a visual learner so I'd say it's best to physically get the books and have a look at it working for yourself if you think that would help you. In the case of animals, a small surface area:volume ratio reduces heat loss because there's less skin (area) exposed around the animal, so a smaller area of skin over which heat can be lost from via radiation. Conversely, a large surface area:volume ratio increases heat loss because there's more skin (area) exposed around the animal, in relation to its size, so there's a larger amount of skin (surface area) by which heat can be lost via radiation.

For example: the elephant. If an elephant had no flaps of skin, it would have the same volume because it would be the same size, but a smaller surface area because there would be less skin around it. Therefore, less heat would be lost via radiation if the elephant had no flaps of skin because, for the same size elephant, less heat is lost from the skin through radiation.

I hope that's helpful, if it's not then I can try and re-word it or find a visualisation. It all links to the amount of heat that an be lost by radiation in animals.

As for the plants in rainforests; I am aware that leaves in rainforests are often thick and shiny to protect from extreme sunlight, however I'm unsure with regards to rain. Leaves coated in grease take in far less water, so I assume it would work in a similar way and attempt to protect the leaf from absorbing too much water. Likewise, I think the pointed tips are designed so that water drips off the leaf quickly after rainfall, which might aid in allowing more sunlight to be absorbed, as that is more in demand that rainfall in the rainforest.

However that is mostly speculation, so don't take my word for it! Hope that helps
(Original post by okey)
It links to P1; you should know that heat is emitted from the surface of an object. A high surface area to volume ratio gives an animal more surface area to emit heat from, letting more heat be emitted and cooling it down. A high volume to surface area ratio will conserve heat due to the smaller surface for heat to be emitted from.
Thank you soo much everyone!! I really understand it!! I absolutely love these detailed explanations as I learn so much that I haven't even learnt in class!! Thanks a tonne!! :P
6. (Original post by Perfection Ace)
Thank you soo much everyone!! I really understand it!! I absolutely love these detailed explanations as I learn so much that I haven't even learnt in class!! Thanks a tonne!! :P

## Register

Thanks for posting! You just need to create an account in order to submit the post
1. this can't be left blank
2. this can't be left blank
3. this can't be left blank

6 characters or longer with both numbers and letters is safer

4. this can't be left empty
1. Oops, you need to agree to our Ts&Cs to register

Updated: May 13, 2016
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Today on TSR

### How does exam reform affect you?

From GCSE to A level, it's all changing

Poll
Useful resources

## Study tools

### Essay expert

Learn to write like a pro with our ultimate essay guide.

See where you can apply with our uni match tool

### Make study resources

Create all the resources you need to get the grades.

### Create your own Study Plan

Organise all your homework and exams so you never miss another deadline.

### Resources by subject

From flashcards to mind maps; there's everything you need for all of your GCSE subjects.

### Find past papers

100s of GCSE past papers for all your subjects at your fingertips.