Gravitation Flashcards
What is force?
The act of push or pull that affects the object.
Define centripetal force.
The force that causes this acceleration and keeps the body moving along the circular path is acting towards the centre. is called centre-seeking force/centripetal force.
Example of centripetal force.
The motion of the moon around the earth. The centripetal force is provided by the force of attraction of the earth.
Why don’t we see the earth moving towards the apple.
According to the third law of motion the apple does attract the earth. But according to the second law of motion, for a given force, acceleration is inversely proportional to the mass of the object.
- mass of apple
What is gravitational force?
All objects in the universe attract each other. This force of attraction between objects is called the gravitational force
State the universal law of gravitation.
Every object in the universe attracts every other object but the force that is proportional to the product of masses of the objects and inversely proportional to the square of distance between them.
What is the SI unit of the universal law of gravitation?
The SI unit of G can be obtained by substituting the unit of force, distance and mass as
Nm²kg⁻²
Who found the value of G?
Henry Cavendish found the value of G by using a sensitive balance. The accepted value of G is
6.673 ⅹ 10⁻¹¹ Nm²kg⁻²
Why is the universal law of gravity also known as inverse square?
- the universal law of gravity can be applied to all parties whether the bodies are big or small, whether they are celestial or terrestrial.
- F it’s inversely proportional to the square of D means that if d gets bigger by factor of 6 F becomes 1/36 times smaller.
Importance of universal law of gravitation.
The universal law of gravitation explained the things that was believed to be unconnected.:-
- The force that binds us to the earth.
- The motion of the moon around the earth.
- The motion of planets around the sun.
- The tides due to moon and the sun.
What is freefall?
When an object falls towards the earth under the force of gravitational force alone we say that the objects are in freefall.
What is acceleration due to gravity?
The earth attracts objects towards it this is due to the gravitational force. Due to this attraction of the earth when an object is under freefall there will be a change in the magnitude of velocity post op any change in the velocity involves acceleration. So whenever an object falls towards the earth and acceleration is involved this acceleration is caused due to earth’s gravitational force. Therefore, this acceleration is called acceleration due to gravity.
SI unit of acceleration due to gravity.
acceleration due to gravity is denoted by “g”. Its SI unit is the same as velocity. m/s².
