scilearner

I certainly have a mental block with this question. I'm not really sure about the answer. It should depend on the plant and the end results. I'm not really sure

yes the radio isotopes will be decaying all the time, but how soe it help the plants grow (assume a non radioactive fertiliser for this part)

A fertilizer is added to soil to improve plants' growth and yield. Fertilizers provide nutrients that are responsible for growth and reproduction of plants.

okay, what happens to the fertilizer after its added to the soil?

The ferilizer decays. Oh do the labels show the decaying rate

Thank you very much for the help everyone. Really appreciate your time and effort to answer these questions.

@Insane Alien: Thank you very much for the answers. I still can't figure out the

second question. Well fertilisers should be added to the soil

before they can affect the growth of a plant. I still don't fully

understand this question.

Hello everyone,

(These questions seem long but the answers are very short. So please read)

I'm going to start biology next year. I was just reading the first chapter of my biology book. I'm finding radioactive isotopes bit hard. These are 3 quick questions in the textbook. These might be very easy, but I'm very new to biology. Your help would be very greatly appreciated. Thank you

1. The Chernobyl disaster involved radioisotope that takes a long time to decay. This is why it created problems for generations to come. If you were choosing a radioisotope to use in medical diagnosis would you choose one with a slow or fast decay?

My guess is fast. Less problems

2. A farmer was offered three types of fertiliser to use on his crop. Explain how isotope labels such as nitrogen-15 and phosphorus-32 could be used to determine the optimum fertiliser for his crop.

3. Radioisotopes are used to treat cancerous growths. How would they exert their effect on a tumour.

My guess tumour cells can be killed by the radiation of radioisotopes

I want to understand the answer so please post an explanation. Thank you very much!!

Done!. It was just a problem in my browser settings. I have put the wrong proxy server. Sorry for the inconvenience. Thanks anyway Ryan J:-)

Hi Guys,

Lately my broadband internet connection is not working properly. It connects and says 1.5 mb connection but when I load a webpage it loads after like 10 minutes. It is nothing to do with bandwith as this is a new month and I have checked my usage. I have USB EXTERNAL ADSL modem. Help would be appreciated.

Thank you:-) . You deserve that picture as your avater.

Ok' date=' think about this (Sorry is my explaing is bad )

 

The center of gravity or any sphere is at its center, the Earth is not a perfect sphere but for simplicity lets pretend it is

 

This center of gravity is where all the gravity created by the mass of the Earth acts.

This tries to pull everything to the center of the Earth and so it creates a greater preassure the closer to the center of gravity you get.

This preassure prevents the inner core from being molten because as you increase preassure it affects the melting and boilling points of objects. Just as lowering pressure lowers the melting point of something, an exaple being water on Everest which boils below 100 degrees C, at really high presures a higher temperature would be needed to melt the solid thus explaining why the inner core is solid

 

Hope that helps,

 

Ryan Jones[/quote']

 

Your explanation is really good but I need to clarify few things. You have stated that high temperature would be needed to melt the solid in the metal core. But isn't the metal core really really hot and thus would be able to melt the solid. Another thing to clarify is that does mt eversest have low pressure because it is high.

Hello everyone,

I just want to know why is the metal core of the earth solid?

I'm a begginer and your help would be appreciated.