## Tuesday, 6 March 2018

### Buoyant force lab

DATA TABLE

 Object Weight in Air Apparent weight in water Buoyant force Volume of displaced water Weight1 0.1 N 0.24 N 0.23N 0.1 ml Weight2 0.2N 0.30N 0.28N 0.2ml Weight4 0.8N 0.6N 0.2N 10ml Weight5 1N 0.8N 0.2N 20ml Weight6 2N 1.75N 0.25N 30ml Weight7 2N 1.75N 0.25N 30ml Weight8 5N 4.20N 0.8N 70ml Weight9 8.5N 6N 2.5N 350ml

1. Observing; What force is responsible for the difference between the weight of each object in the air and its apparent weight in water? - Buoyant force
2. How is buoyant force related to the weight of water displaced? -Buoyant force is equal to the weight of the displaced water.
3. Define buoyant force and describe two ways you can measure it or calculate it. -the upward force exerted by any fluid upon a body placed in it. -Weight in air decrease by weight in the water. -Buoyant is equal to weight of fluid that object displace.
4. Explain what causes an object to sink or to float, using the terms buoyancy, weight, force, density and gravity. -Gravity pulls object with greater density downward. -Objects float is that at any depth in a fluid there is an upward force due to the effect of gravity on the fluid.                 -Downward force, due to its weight, is greater than the upward force of the water at that depth.

## Wednesday, 14 February 2018

### Plaifa-Electric charge lab

Launch LabHow can you bend water?

1. Infer Why did you rub the balloon on your hairPredict what might have happened if you simply touched the balloon to your hair instead of rubbing it.
Ans : When you rub balloon through your hair, tiny parts of the atoms in your hair, called electrons, collected on the balloon. These electrons have a negative charge. Now that the balloon has a negative charge, it is attracted to things that have a positive charge (water). It is similar to the way some magnets are attracted to certain metals.
2. Key Concept Why do you think the balloon interacted the way it did with your hair and with the stream of water?
Ans : When you bring the negatively charged balloon near the water that you pour it is attracted to the positive force of the water. The attraction is strong enough to actually pull the water towards the balloon as it is flowing.

## Wednesday, 22 November 2017

Light LAB
Activity A:
1. look at the monitor
2. r+g, r+b, b+g
3. work with another group—put a color paddle over
flashlight, shine on white paper—so a red, a green,
and a blue
Activity b
3. view white paper through color paddles—record
results
4. view colored objects through color paddles
5. if you have time, do activity b—color by
subtraction--

Red+Green=Orange light (almost like brown color)
Red+Blue=Red purple light
Blue+Green=Blue light
Red+Green+Blue= White light

And after doing the light experiment our group have come up with a new LAB idea which is to use many colors of paddles to try to look through a 3D picture. Which the result is that only red and blue paddles can look through to make a 3D picture. After we done with both experiment (Light LAB, 3D LAB) the other group and Kru Gary started to do the same thing (3D LAB) as we do.

## questions

1)  why do we add salt to the ice? To make the milk freeze into an ice-cream. ^-^

2)   why do we add the cookies and other things, only after the milk has frozen slightly? Because if we add other things into milk before it frozen slightly then the milk will not freeze, but if we put the other things into the milk when it already freezes then the other stuff and milk will not mix together.

3)  what are two factors that affect the freezing you think?
Ice and salt because salt cools down the temperature of the ice down and makes the milk become an ice cream.

4)  why do you need a bit of air in the bag? Because it will make the ice-cream smoother and softer not so hard until become solid.

## My favorite lesson in Add science class

My favorite lesson in Add science class in grade 8 is the lesson about the about the structure of the Earth because I like to learn and know what is inside our world! And I have learned about it make me know much more new stuff the class was so interesting I have know that there are 3 Earth layers: crust, mantle and core. But the most thing I like in this class is the teacher. I like Kru Gary. He is a great teacher. Thank you for being our great teacher.

## Volume, Mass and Density Lab

Volume is the amount of space occupied by a three-dimensional object or region of space.

Mass is a measurement of how much matter is in an object.

Density is a measure of mass per volume.