Fluids
Which of the following best describes an open fluid system?
A system that exchanges both matter and energy with its surroundings.
A system that exchanges energy but not matter with its surroundings.
A system that exchanges matter but not energy with its surroundings.
A system that exchanges neither matter nor energy with its surroundings.
A rock has a mass of 600 kg and a volume of 0.3 m³. What is the density of the rock?
200 kg/m³
600 kg/m³
180 kg/m³
2000 kg/m³
A wooden block has a density of 700 kg/m³ and a volume of 0.05 m³. If the block is placed in water with a density of 1000 kg/m³, what volume of the block will be submerged?
0.020 m³
0.035 m³
0.050 m³
0.071 m³
How does density generally change with increasing temperature?
Density increases.
Density decreases.
Density remains constant.
Density fluctuates randomly.
What is the SI unit for pressure?
Newton (N)
Pascal (Pa)
Kilogram (kg)
Meter (m)
A force of 50 N is applied over an area of 2 m². What is the pressure?
25 Pa
50 Pa
100 Pa
200 Pa
A 2 kg object is submerged in water. The buoyant force acting on the object is 10 N, and the drag force is negligible. What is the net force acting on the object?
0 N
10 N downward
10 N upward
20 N downward

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Which forces should be included in a free-body diagram for an object submerged in a fluid?
Weight only
Buoyancy only
Weight and buoyancy only
Weight, buoyancy, and drag (if applicable)
An object is floating in a fluid. Which statement is true regarding the forces acting on the object?
The weight is greater than the buoyant force.
The weight is less than the buoyant force.
The weight is equal to the buoyant force.
The buoyant force is zero.
A 0.1 m³ object is submerged in a fluid with a density of 1200 kg/m³. What is the buoyant force acting on the object?
120 N
1200 N
- 176 N
12000 N