Chapter 7.3 Q & A
1. (a) In your own words, define “flow rate” and “viscosity.”
The flow rate of a fluid at how quickly it’s able to pass a certain point in a given amount of time. It’s
the term used to describe the speed of a fluid. Viscosity is when we are referring to the thickness of a
fluid, or rather, its resistance to flow.
(b) Describe the relationship between flow rate and viscosity.
Flow rate refers to volume of a fluid and how fast it can move past a certain point in a given amount of
time. Viscosity is basically the term we use opposed to flow rate. Viscosity is used to talk about the
resistance of flow, or thickness. The relationship between them is like the fast and slowness of a fluid.
They both are terms used to describe a certain factor of a fluid that has to do with either volume or
thickness/speed.
2. In your own words, define “cohesion” and “surface tension.”
Cohesion talks about the force of attraction between the particles of a substance. A thicker fluid will
have a slower rate, and will most likely contain particles with greater cohesion. Surface tension refers to
the cohesion of particles on a liquid’s surface. It’s a strong attraction among particles that form the
surface of a liquid.
3. Use the term “viscosity” to explain how wetting agents are used to help fight fires.
When wanting to fight against fires with water, you would want less cohesion in the water. If the
viscosity of the water is lower than it usually is, it would hit the tree’s with fire first and it would allow
for the water to fight the fire faster. It would also spread amongst the trees faster.
4. (a) How does adhesion affect flow rate?
Adhesion is the force of attraction between particles of a fluid and particles of other substances.
(b) Give an example in real life that shows adhesion at work.
When you drink milk out of a cup, some particles will stick to the glass because of adhesion. Adhesion
being the force of attraction between the milk and the side of the glass.
1. (a) In your own words, define “flow rate” and “viscosity.”
The flow rate of a fluid at how quickly it’s able to pass a certain point in a given amount of time. It’s
the term used to describe the speed of a fluid. Viscosity is when we are referring to the thickness of a
fluid, or rather, its resistance to flow.
(b) Describe the relationship between flow rate and viscosity.
Flow rate refers to volume of a fluid and how fast it can move past a certain point in a given amount of
time. Viscosity is basically the term we use opposed to flow rate. Viscosity is used to talk about the
resistance of flow, or thickness. The relationship between them is like the fast and slowness of a fluid.
They both are terms used to describe a certain factor of a fluid that has to do with either volume or
thickness/speed.
2. In your own words, define “cohesion” and “surface tension.”
Cohesion talks about the force of attraction between the particles of a substance. A thicker fluid will
have a slower rate, and will most likely contain particles with greater cohesion. Surface tension refers to
the cohesion of particles on a liquid’s surface. It’s a strong attraction among particles that form the
surface of a liquid.
3. Use the term “viscosity” to explain how wetting agents are used to help fight fires.
When wanting to fight against fires with water, you would want less cohesion in the water. If the
viscosity of the water is lower than it usually is, it would hit the tree’s with fire first and it would allow
for the water to fight the fire faster. It would also spread amongst the trees faster.
4. (a) How does adhesion affect flow rate?
Adhesion is the force of attraction between particles of a fluid and particles of other substances.
(b) Give an example in real life that shows adhesion at work.
When you drink milk out of a cup, some particles will stick to the glass because of adhesion. Adhesion
being the force of attraction between the milk and the side of the glass.
