CHAPTER 9 GRAVITATION 9th class JN PURAM

9.1 what is gravitation? page28 Indhu.A

• Gravitation is the force of repulsion between two objects with mass.
• Gravitation is the force of attraction between two objects with mass.
• Gravitation is the force of attraction between two objects with charge.
• Gravitation is the force of attraction between two objects with temperature.

9.1.1 universal law of gravitation page30 kotesh.G

• Every point mass attracts every other point mass in the universe with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.
• Objects attract each other with a force that is directly proportional to the square of the distance between their centers
• Gravity only affects objects on Earth
• The force of gravity is not related to the masses of the objects

9.4.1 what is the weight of an object on the moon? Page38 Pawan.A

• 25% of the object's weight on Earth
• 50% of the object's weight on Earth
• 10% of the object's weight on Earth
• 16.5% of the object's weight on Earth

9.2 what is free fall?page32 sanjana.P

• Free fall is the motion of an object where magnetism is the only force acting upon it.
• Free fall is the motion of an object where air resistance is the only force acting upon it.
• Free fall is the motion of an object with no gravity acting upon it.
• Free fall is the motion of an object where gravity is the only force acting upon it.

9.5 what is thrust and pressure? page40 chiranjeevi .K

• Thrust is the force exerted perpendicular to the surface of an object due to the motion of fluid or gas. Pressure is the force exerted perpendicular to the surface of an object due to the weight of the fluid or gas above it.
• Pressure is the force exerted perpendicular to the surface of an object due to the motion of fluid or gas.
• Thrust is the force exerted perpendicular to the surface of an object due to the weight of the fluid or gas above it.
• Thrust is the force exerted parallel to the surface of an object due to the motion of fluid or gas.

pressure in fluids

• Pressure = Work / Time
• Pressure = Volume / Area
• Pressure = Force / Area
• Pressure = Density / Volume

9.5.3. why objects float or sink when placed on the surface of water? page44 Sivasai.S

• Objects float or sink based on their shape compared to the shape of water.
• Objects float or sink based on their temperature compared to the temperature of water.
• Objects float or sink based on their color compared to the color of water.
• Objects float or sink based on their density compared to the density of water.

9.6 Define Archimedes principle? Activity9.7 page46 sanjana.V

• The weight of an object is equal to the volume of the object.
• The volume of an object is equal to the weight of the object.
• Buoyant force equals weight of displaced fluid.
• Density of an object is equal to the weight of the object.

9.3.2 What is terminal velocity? Page 36 Ramesh.K

• Terminal velocity is the maximum velocity an object reaches when falling through a fluid, such as air or water, due to the balance between gravity and air resistance.

• Terminal velocity is the velocity at which an object stops moving in a fluid due to the absence of gravity.

• Terminal velocity is the velocity at which an object accelerates infinitely due to the absence of air resistance.

• Terminal velocity is the velocity at which an object reaches when falling through a vacuum.

9.2.1 What is the difference between mass and weight? Page 34 Harsha.M

• Mass is the amount of matter in an object, while weight is the force of gravity acting on an object's mass.

• Mass and weight are the same physical quantity measured in different units.

• Mass is the force of gravity acting on an object, while weight is the amount of matter in an object.

• Mass and weight have no relation to each other.