Mix and Flow of Matter Flashcards
Use the particle model of matter to explain what would have to happen in a sealed container of molasses to make the container explode.
If you heat up the container, the particles would start moving faster, finally changing into a gas. Gases take up way more space than liquids, so pressure would build up and cause it to explode
Use the particle model to explain why solids have a definite shape.
Particles in a solid vibrate around fixed locations, and the strong attractions between the particles in a solid restrict their motion, keeping them in place.
Identify three occupations in which knowledge of viscosity is important. For each, describe how the knowledge is applied.
Examples include:
Mechanics - motor oils
Engineers - designing machines engines need to know about lubricants
Pipeline workers - need to know how temperature affects flow of liquids
What is the relationship between the flow rate of a liquid and its viscosity?
The Thicker fluids flow slower.
The Thinner fluids flow faster.
High viscosity means high resistance to flow, and low viscosity means low resistance to flow.
What is the density of a substance that has a volume of 50 mL and a mass of 63 g? Show how you calculated the answer, including the formula you used.
D = mass ÷ volume
= 63 g ÷ 50 mL = 1.26 g/mL
Describe the difference between the particles of a dense substance and the particles of a light substance.
Particles in a dense substance are going to be closer together, and the particles themselves could be heaver as well.
Particles in a light substance are going to be further away, and the particles could be lighter.
Why is it easier to do a handstand in a swimming pool than in a gymnasium?
Because the pressure of the water holds you in place.
You are helping to clear rocks from a swimming area at a cottage. Using your knowledge of buoyancy, suggest a way to make the rocks easier to move around. Explain why your method would work.
You could find a floating mat or something similar that floats, and put a few rocks on it. Then you would drag the mat through the water where you want the rocks to go. This would work because its easier to move things around in water, and using the mat would make things even easier.
Explain why water pressure on a submersible increases as it sinks deeper underwater.
Because the weight of the water above pressing down, and causes there to be more pressure the deeper you go.
You have just completed an investigation in which you poked holes in a milk carton full of water to show that water pressure increases with depth. How would you modify the procedure to demonstrate that a liquid at rest exerts pressure equally in all directions?
You could poke holes in 4 sides at equal heights, on all sides of the carton.
What is the difference between force and pressure?
A force can be a push or a pull. When a force is exerted on an object it can change the object’s speed, direction of movement or shape. Pressure is a measure of how much force is acting upon an area.
List three examples of hydraulic machines.
- Excavator.
- Airplanes (some parts of airplanes run on hydraulics).
- Bulldozers.
List three examples of pneumatic machines or devices.
- Air Brakes.
- Dental Drill.
- Nail Gun.
Give a reason for not using water in hydraulic systems.
Water causes rust and it is very thin so it could leak. Oil is usually used because it is a lubricant and does not cause corrosion.
What function do valves perform in the human circulatory system?
Heart valves control blood in and out of the heart.
