Physics ยท Science General
Newtonian Mechanics and Forces
1,559 Questions
Newtonian mechanics studies the motion of objects and the physical laws governing them. This hub covers friction, gravitational force, inertia, and vector quantities. Mastering these fundamental physics concepts is essential for various government competitive exams.
Laws of motionFriction and inertiaVector and scalar quantitiesGravitational accelerationArchimedes principle
Newtonian Mechanics and Forces Questions
Which of the following is NOT a common disturbance that can affect spacecraft attitude control?
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Gravity gradient torques
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Aerodynamic torques
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Solar radiation pressure
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Magnetic field disturbances
D
Correct answer
Explanation
Gravity gradient torques, aerodynamic torques, and solar radiation pressure are common disturbances that can affect spacecraft attitude control. Magnetic field disturbances are not typically a significant concern.
Which of the following is NOT a fundamental force in physics?
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Gravitational Force
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Electromagnetic Force
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Strong Nuclear Force
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Frictional Force
D
Correct answer
Explanation
Frictional force is not a fundamental force in physics. It is an emergent force that arises from the interaction of matter at the macroscopic level.
What is the force that pulls objects towards the center of the Earth?
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Gravity
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Magnetism
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Electromagnetism
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Centrifugal Force
A
Correct answer
Explanation
Gravity is the force that attracts objects with mass towards each other. It is what keeps us on the ground and causes objects to fall when dropped.
What is the primary force that opposes the motion of a ship through water?
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Gravity
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Buoyancy
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Drag
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Inertia
C
Correct answer
Explanation
Drag is the primary force that opposes the motion of a ship through water, acting in the opposite direction of the ship's movement.
What is the term used to describe the upward force exerted by water on a floating object?
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Buoyancy
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Upthrust
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Hydrostatic force
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Archimedes' principle
A
Correct answer
Explanation
Buoyancy is the upward force exerted by water on a floating object, equal to the weight of the water displaced by the object.
The metacentric height (GM) of a ship is a measure of its:
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Stability
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Trim
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Freeboard
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Displacement
A
Correct answer
Explanation
Metacentric height (GM) is a measure of a ship's initial stability, indicating its resistance to heeling over when subjected to external forces.
What is the term used to describe the angle at which a ship tilts when subjected to external forces?
A
Correct answer
Explanation
Heel is the angle at which a ship tilts to one side when subjected to external forces, such as wind or waves.
Which of the following is a type of ship resistance caused by the pressure difference between the front and rear of the hull?
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Skin friction resistance
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Viscous resistance
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Wave-making resistance
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Pressure resistance
D
Correct answer
Explanation
Pressure resistance is a type of ship resistance caused by the pressure difference between the front and rear of the hull, resulting from the acceleration of water around the hull.
What is the term for the force exerted by a fluid (such as water) on an object moving through it?
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Drag
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Lift
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Thrust
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Resistance
A
Correct answer
Explanation
Drag is the force that opposes the motion of an object through a fluid, caused by the interaction between the object and the fluid.
What is the term for the force that opposes the motion of an object through a fluid, caused by the pressure difference between the front and back of the object?
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Drag
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Lift
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Thrust
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Resistance
Correct answer
Explanation
Pressure drag is the force that opposes the motion of an object through a fluid due to the pressure difference between the front and back of the object.
What is the term for the force that opposes the motion of an object through a fluid, caused by the viscous properties of the fluid?
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Drag
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Lift
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Thrust
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Resistance
Correct answer
Explanation
Viscous drag is the force that opposes the motion of an object through a fluid due to the viscous properties of the fluid, causing friction between the object and the fluid.
What is the primary factor that determines a ship's stability?
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Hull shape
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Weight distribution
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Center of gravity
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Buoyant force
C
Correct answer
Explanation
The center of gravity (CG) of a ship is the point at which the entire weight of the ship acts. The stability of a ship depends on the relationship between the CG and the center of buoyancy (CB).
What is the effect of increasing the GM on a ship's stability?
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It increases the ship's stability
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It decreases the ship's stability
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It has no effect on the ship's stability
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It depends on the loading condition
A
Correct answer
Explanation
Increasing the GM increases the ship's initial stability. However, it can also make the ship more tender, which means that it will roll more easily.
What is the effect of moving the CG higher on a ship's stability?
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It increases the ship's stability
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It decreases the ship's stability
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It has no effect on the ship's stability
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It depends on the loading condition
B
Correct answer
Explanation
Moving the CG higher decreases the GM, which in turn decreases the ship's initial stability.
What is the effect of adding weight to a ship on its stability?
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It increases the ship's stability
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It decreases the ship's stability
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It has no effect on the ship's stability
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It depends on the location of the added weight
D
Correct answer
Explanation
Adding weight to a ship can increase or decrease its stability, depending on the location of the added weight. Adding weight high up on the ship will decrease its stability, while adding weight low down will increase its stability.