Fluids and Viscosity
What two states of matter are fluids?
LIQUIDS and GASSES
What is the formula to calculate density?
D = m/v
Density = mass / volume
TRUE OR FALSE
An object which has a density that is HIGHER than the density of water means it has POSITIVE buoyancy
FALSE
Negative buoyancy = object has density more than water (density ratio is greater than 1)
Compressability is the ability to put ______ on a fluid or substance?
a) Heat
b) Pressure
c) Weight
d) Volume
Pressure
Which is the following is NOT a factor which affects the viscosity of fluids
a) Friction
b) Adhesion / Cohesion
c) Mass
d) Temperature
MASS (does not directly affect viscosity)
The main factors affecting viscosity are...
- Friction, adhesion/cohesion and temperature
The measure of the force of gravity acting on an object is best described as...
a) Mass
b) Weight
c) Viscosity
d) Acceleration
Weight
Double Points!
This state of matter is the LEAST compressible
This state of matter is the MOST compressible
Solids = LEAST compressible
Gas = MOST compressible
Low flow rate means.... __________ viscosity
HIGH viscosity
You have a rock with a volume of 15cm3 and a mass of 45 g. What is its density?
The density is 3.0 g/cm3
What happens when the buoyant force acting on an object is GREATER than the objects weight?
The object will FLOAT
Why are gasses more compressible than liquids?
There is less space between particles in a liquid, and gasses have more space between their particles which makes them easier to compress
Double Points!
What does increasing temperature of a liquid do to its viscosity and flow rate? (e.g., warming up cold water)
DECREASE viscosity, INCREASE flow rate
An object will float in water when it's density is ________ than the density of water
LESS than the density of water
Who was the scientist who first discovered the amount of fluid displaced by an object is equal to its volume and created a scientific principle to explain this relationship
a) Sir Isaac Newton
b) Pascale
c) Archimedes
d) Pythagoreas
Archimedes
Double Points!
Gas is used to power __________ systems and Liquids are used to power ___________ systems.
a) Hydraulic systems
b) Solar systems
c) Electric systems
d) Pneumatic systems
GAS = Pneumatic
LIQUID = Hydraulic
What does increasing the temperature do to the viscosity of a gas?
BONUS (200): Explain why the increase in temperature changes the viscosity of a gas
INCREASES viscosity, DECREASE flow rate
BONUS: Increasing the temperature in a gas causes the particles to move faster... This causes more FRICTION because they are colliding more often. Greater friction between particles means higher viscosity
The density of gold is 0.01932 kg/cm3. How much mass would a brick of gold with a volume of 1000 cm3 have? (give your answer in grams)
What is 19320 g?
Neutral buoyancy means... the buoyant force equals the weight of the object, so the object neither sinks nor floats—it just hovers or remains suspended in the fluid
Give a real world example of something which uses Neutral buoyancy
- Fish with swim bladders
- Scuba divers
- Submarines
- Astronaut training (simulating weightlessness in space)
Describe in your own words what is Pascal's Law
When pressure is exerted on a fluid, it will be evenly distributed throughout the fluid (in all directions)