This page covers following concepts and contains physics MCQs from these topics.

• Viscous Drag and Stokes law.
• Archimedes Principle.
• Terminal Velocity.
• Fluid Flow.
• Equation of continuity.
• Bernoulli’s Equation.
• Application of Bernoulli’s Equation.
• Torricelli’s Theorem.
• Relation between speed and pressure.
• Blood Flow and Venturi Relation

Q1. An object is thrown in upward direction in air, before reaching to maximum height the magnitude of net force on the object is
A) Weight
B) Drag force
C) Weight + drag force
D) Weight – drag force

Q2. The value of drag force can be calculated by using
A) Bernoulli’s equation
B) Stokes law
C) Pascal’s law
D) None of the above

Q3. Drag force on an object is independent of which of the following
A) Speed of object
B) Cross sectional area
C) Shape
D) None of the above

Q4. An object is allowed to fall freely in the downward direction through air. keeping account of air friction the net force on the object will
A) Increase
B) Decrease
C) First increase then decrease
D) Remains same

Q5. An object is dropped from a high building (without ignoring air friction) the acceleration of the stone during falling will
A) Increase
B) Decrease
C) Remains Same
D) First increase and then decrease

Q6. If a Bullet is fired in the downward direction and its muzzle velocity is greater than its terminal velocity in air. The velocity of bullet after leaving the gun will
A) Increase
B) Decrease
C) First decrease and then increase
D) First increase and then decrease

Q7. When any object is falling with terminal velocity the net force on it is
A) Equal to its weight and downward
B) not equal to weight but downward
C) zero
D) upward

Q8. Two spheres of same radius but different mass are moving through a fluid with same velocity the drag force is
A) more on heavy sphere
B) less on heavy sphere
C) same on both spheres
D) More information is required

Q9. Two spheres of same radius but different mass are falling through a fluid which of them will have higher value of terminal velocity
A) Heavy sphere
B) Light sphere
C) Both will have same terminal velocity
D) More information is required

Q10. An object falling with terminal velocity is example of
A) Newton’s first law as net force is zero and object is moving with uniform velocity
B) Newton’s Third law as drag force and weight of object are equal
C) Both A and B
D) None of above

Q11. For an object floating on the surface of a liquid. The liquid displaced by object is equal to complete object by
A) Volume
B) Weight
C) both volume and weight
D) None of the other options is correct

Q12. For an object completely submerged and lying on bottom surface of liquid. The liquid displaced by object is equal to complete object by
A) Volume
B) Weight
C) both volume and weight
D) None of the other options is correct

Q13. For an object partially submerged in water and lying on bottom surface of liquid. The liquid displaced by object is equal to complete object by
A) Volume
B) Weight
C) both volume and weight
D) None of the other options is correct

Q14. A piece of ice of irregular shape is floating in beaker of water kept at 0 degree Celsius. When Ice melts the level of water will
A) Rise
B) Fall
C) Remain same
D) Depends on the shape of piece of ice

Q15. A cuboid will whose density is less than the density of liquid will immerse least in liquid when place along
A) Face with minimum base area down
B) Face with intermediate base area down
C) Face with maximum base area down
D) It does not depend on which face is down

Q16. A cube is placed in two liquids of different densities float on both of them. In first liquid 60% of the cube is outside liquid and in second liquid 80% of cube is outside the liquid. The ratio in the densities of fluids is
A) 1:2
B) 2:1
C) 3:4
D) 4:3

Q17. An object is floating on water and its 60% volume is inside the liquid. If weight of the object is 30 N the force required to completely submerge in water will be
A) 20 N
B) 30 N
C) 40 N
D) 60 N

Q18. An object is floating on water inside a bucket and its 50% volume is inside the liquid. If the bucket is placed inside a lift and lift is accelerated in upward direction with acceleration twice of g which of the following will be true.
A) Object will completely immersed in water
B) only 17% of the object will remain immersed in water
C) 83 % of the object will be immersed in water
D) None of the above options is correct

Q19. An object is floating on water and displace 15 N of fresh water if we increase the density of water by adding salt the object will displace how much salt water
A) 15 N
B) Less than 15 N
C) More than 15 N
D) Depends on quantity of salt

Q20. An object is floating on water if we increase the density of water by adding salt the object will move in which direction relative to water surface.
A) Upward
B) Downward
C) Remains same
D) First upward than downward

Q21. An object which is immersed completely in water when weighed on spring scale will show
A) less weight than real weight
B) less weight than real weight
C) same weight as real weight
D) May show less or more weight depends on value of g

Q22. An object whose real weight is 20 N when weight is measured when object is completely dipped in water is 12 N the density of object relative to water density is
A) 0.4
B) 0.6
C) 1.5
D) 2.5

Q23. A plastic bottle total outside volume is 1200 cm^{3} and its mass is 200 grams. How much sand can be added into bottle before drowning
A) 800 grams
B) 1000 grams
C) 1200 grams
D) 1400 grams

Q24. Two objects of different shapes when completely dipped in water experience same upthrust which of the following parameter is same for both objects
A) Density
B) Volume
C) Mass
D) Cross sectional area

MCQs 25-30 A container is lying on a horizontal floor. The level of water in the container is upto height H. A hole is formed on one side above height a from the surface as shown in figure.(Assume water to be non viscous)

Q25. The velocity of water coming out of hole will be
A) \sqrt{2gH}
B) \sqrt{2ga}
C) \sqrt{2g(H+a)}
D) \sqrt{2g(H-a)}

Q26. The horizontal distance covered by water before falling on floor will be
A) \sqrt{aH}
B) 2\sqrt{aH}
C) \sqrt{a(H-a)}
D) 2\sqrt{a(H-a)}

Q27. If we want to maximize the horizontal distance of water stream we should make hole at what height above the lower surface of water
A) H
B) \frac{2H}{3}
C) \frac{H}{2}
D) \frac{H}{3}

Q28. Another stream from another hole covers same horizontal distance the height of the other hole will be
A) H
B) H-a
C) H-2a
D) H-\frac{3a}{2}

Q29. If water is replaced by some other non-viscous liquid with lower density the horizontal distance covered by the stream from the same hole will
A) Decrease
B) Increase
C) Remain same
D) Depend on size of hole

Q30. In the above container pressure is measured at different points all lying exactly same height a from the bottom. The pressure will be
A) Same at all points
B) Lower near the hole
C) Higher near the hole
D) We need more information

Q31. A bird of weight 10 N is in a air tight cage of weight 20 N. If put the cage on weighing scale, the weight measured by the scale when bird is flying inside the cage will be
A) 10 N
B) 20 N
C) 30 N
D) 40 N

Q32. Equation of continuity is applicable to
A) Viscous and incompressible fluid
B) Non-viscous and incompressible fluid
C) Compressible and non-viscous fluid
D) Both A and B

Q33. Equation of continuity is based on law of conservation of
A) mass
B) Energy
C) momentum
D) Both A and B

Q34. In a horizontal pipe of uniform diameter a plastic bag is stuck in the middle, the bag blocked 75% of cross sectional area of the pipe. The speed of flow through remaining area will be
A) Same as in other parts of pipe
B) Lower than other parts of pipe
C) Higher than other parts of pipe
D) May be lower or higher than other parts of pipe

Q35. Hydraulic press work on the principle of
A) Equation of continuity
B) Bernoulli’s equation
C) Pascal’s law
D) Archimedes principle

Q36. Uplift of airplane is based on the principle of
A) Equation of continuity
B) Bernoulli’s equation
C) Pascal’s law
D) Archimedes principle

Q37. The relative density of an object can be calculated by
A) Equation of continuity
B) Bernoulli’s equation
C) Pascal’s law
D) Archimedes principle

Q38. Venture meter is used to measure
A) Flow rate of fluid
B) Pressure of fluid
C) Density of fluid
D) None of the above

Q39. Values of systolic and dia-systolic pressure for healthy human being are respectively
A) 120 mm of Hg and 80 mm of Hg
B) 80 mm of Hg and 120 mm of Hg
C) 120 Pascal and 80 Pascal
D) 80 Pascal and 120 Pascal

Q40. Bernoulli’s Equation is based on
A) Law of conservation of mass
B) Law of conservation of momentum
C) Law of conservation of energy
D) None of the above

Q41. A rigid pipe is completely filled with a fluid. More fluid is entering into the pipe than leaving. One can conclude that
A) Fluid is compressible
B) Entrance hole is bigger than exit hole
C) Velocity of fluid at entry point is higher than exit point
D) None of the above

Q42. A Bus with its windows open is moving at high speed the pressure inside the bus
A) is less than atmospheric pressure
B) is higher than atmospheric pressure
C) is same as atmospheric pressure
D) None of the above

Q43. A skein is suspended in the air. If we blow a stream of air near the skein it move towards the air stream. This motion is based on principle of
A) Surface tension
B) Bernoulli’s principle
C) Equation of continuity
D) None of the above