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Subject:


Subject: Life Sciences
Posted by M.Bradley

How does progesterone and oestrogen play a role in the period of ovulation and menstrual cycle and lutenising hormone,fsh ?
Mindset has really useful notes on Human Reproduction:
http://learn.mindset.co.za/sites/default/files/resourcelib/emshare-show-note-asset/1897_fdoc.pdf

Please be aware of malicious links that may be posted, the full adress name is pasted here for you to see.

Answered by Maryam K



Subject: Life Sciences
Posted by Kwazi

whats the difference between the control and the experiment?
In an experiment, the control group is the unchanged group and has normal conditions
whereas the experimental group has one variable changed so we can see the result.
The experimental group is compared to the normal/ control group

formal definition: A control group in a scientific experiment is a group separated from the rest of the experiment where the independent variable being tested cannot influence the results
Answered by saajid amra



Subject: Chemistry
Posted by Kwazi

where can i get grade 11 chemistry notes and some examples just like the physichs
From the homepage, click on DualView.
Then choose Physical Science Grade 11.
Past papers.
Answered by V. Gokal



Subject: Physics
Posted by Kwazi

what exactly guides you when describing the deffraction pattern?
All diffraction patterns have the same description. If you use red light light, then red and dark. Blue light, then blue and dark. But with red, the bands are wider since red has a larger wavelength.
Answered by V. Gokal



Subject: Physics
Posted by Kwazi

How can one describe a pattern observed on a Monochromatic light of wavelength 650nm passing through a single slit?
A broad central band of bright light is observed, flanked by alternate light and dark bands, getting progressively dimmer.
Answered by V. Gokal



Subject: Technology
Posted by MARIC FLAWS

How does today's technology influence the technology of tomorrow
Answered by Pending

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Subject: Physics
Posted by Kuzwayo

I would like to know how are black holes created and can they be destroyed.

Answered by Pending

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Subject: Physics
Posted by M.Bradley

How to master physics questions based on Newton's and work energy .is there any difference between the two ?
Yes, a major difference indeed!
Please click on the Physical Science link from the homepage, and go to those specific topics. You can contact me directly by direct message from the My Messages section. Look for my name.
Answered by V. Gokal



Subject: Social Science
Posted by BAHATI

discus are the roles of mass media in kenya today?
Answered by Pending

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Subject: Mathematics
Posted by M.Bradley

Help me factorise this equation 2cos^2+4sinxcosx+1=0
Hi

This is answered by a colleague, Mr. S. Deonarain.

Please contact us for any inappropriate content.

Answered by V. Gokal



Subject: Physics
Posted by Abigail

Does vapour pressure affect dynamic equilibrium.Explain fully
yes,according to the Le chatelier's principles,the equilibrium will move(change the position)in order to withstand/reduce the pressure in the system.example,in this case of having more molecules on the right hand side than on the left side,increasing pressure will cause the equestion to move to the left side to balance the pressure molecule and vice-versa
Answered by enock apwoka



Subject: Life Sciences
Posted by M.Bradley

What is the influence of isolating mechanisms?
Isolating mechanism is a form of sympatric speciation. (Formation of a new species due to a mechanism of reproductive isolation). This does not allow for the reproduction bet diff species to take place due to: Temporal isolation, courtship behaviour, Adaptations to different Pollinating Agents, prevention of fertilisation because of diff copulatory organs and hybrid infertility.

PS: will email you more info on it, if I have your email address???

Answered by Madam Eve



Subject: Mathematics
Posted by NOEL

What are some of the basics to approach a hyperbola and parabola function given the graphs drawn in the same axes?
Answered by Pending

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Subject: Physics
Posted by Mohamed Abbas

Hi Mr gokal.....what's your WhatsApp number
Hi
Cannot put it here.
Email me.
Address is at bottom of your worksheets.
:-)

Please contact us for any inappropriate content.

Answered by V. Gokal



Subject: Physics
Posted by Hussain Basha

What are a few examples of Action-reaction pairs and what are the properties of action-reaction pairs? Thanks
The forces are of the same magnitude, act in opposite directions on different objects.
Since they act on different objects, they obviously cannot cancel out.

Every force has a reaction force, which is sometimes not very obvious.

Easy examples:
rocket taking off -
rocket applies force on gas, and gas applies force on rocket.
(rocket and gas takes off in opposite directions!)

firing a gun -
gun applies force on bullet, and bullet applies force on gun (hence gun recoils)
(bullet and gun takes off in opposite directions)
(this can get a little complex if you start thinking about the compression gases, but this is an ok explanation)

Answered by V. Gokal



Subject: Physics
Posted by nthabi

an unknown mass x of sodium carbonate is dissolved in a 200 cubic centimetres of distilled water. in a titration15 cubic centimetres of the solution was used to neutralise 24 cubic centimetres to neutralise 24 cubic centimetres if a 0.12 mol.dm3 hydrochloric acid solution.1. determine the concentration of sodium chloride solution?2. calculate the unknown mass x?3. what is the appropriate indicator for the solution.
1.
sodium chloride concentration? You sure? (0,07 mol.dm-3)

2.
2,0352g

3.
strong acid + weak base
indicator = methyl orange

(i will check with the developers if images can be allowed here. Then I will upload my full solution.)
Answered by V. Gokal



Subject: Mathematics
Posted by tebatso

is zero a number? If zero is a number why they say that any number to the exponent zero is one, but when you use zero to the exponent zero it gives you error?
This is a very long explanation!
Regarded as indeterminate.

Google it. You get some crazy explanations!
Answered by V. Gokal



Subject: Physics
Posted by karin H kelder,Derick Govender and Jagathesan Govender

Explain briefly hw doppler effect functions nd what it may be used for?
example:
If a car approaches with a siren on, each new pulse from the siren has a shorter and shorter distance to travel to reach you (the car is getting closer to you). This creates a higher frequency of pulses for the listener. Hence a higher frequency is heard.

Uses include:
1) to measure the rate of blood flow
2) or the heartbeat of a foetus in the womb
3) speed traps (radar type)
4) used to measure the speed at which stars and galaxies are approaching or receding from us
Answered by V. Gokal



Subject: Mathematics
Posted by Faaizah Kader

Some take pi as 22/7 which will be termed a rational number. Some take it as 3.14.... non-recurring or non-terminating. That be irrational.Question to anybody interested in answering: What do we classify pi as??? Which value do we introduce from point of initiating it's use?P.N: Grades 8 and 9 learners do not use programmable calculators that have the pi button.
Pi is rational. An answer to my own question.
Answered by Faaizah Kader



Subject: Physics
Posted by V. Gokal

To use DualView ....
preferred browsers
1) Chrome (all OS)
2) Edge (Windows 10)

Answered by Pending

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