Forces and Motion Flashcards
What is force?
Force is an external cause that the body experiences as a result of interacting with another body. It is a push or pull effect.
What is effect does the result of a force have on
Force can cause an object to either change its state, direction or its acceleration.
Is force scalar or vector?
Vector as it has both magnitude and direction.
What is the condition for a force to be created?
Two or more things interacting with each other.
What is the unit of force
Newton
What is a Newton?
1 Newton force is the force required to accelerate a mass of 1kg by 1m/s in the direction of applied force.
What is the CGS system?
Centimeter-gram-second unit system
What is the unit of force in the CGS system?
Dyne
What is the dimensional formula of force?
ML𝑇^2
What effects do force have on an object?
Force can Change the Shape and Size of an Object
Force can Change the direction of an Object
Force can Change the Speed of an Object
Force can change the state of Rest or Motion of an Object
What is the formula for force?
Force is defined by the product of the mass and acceleration of the object. For a body with mass “m” and the acceleration “a” the force can be calculated as F=ma
How is resultant force calculated?
When two individuals apply force in the same direction, the resultant is the sum of two forces.
When force is applied in the opposite directions, the resultant is subtracted.
What does the magnitude of a force express?
Its strength
When are forces said to be balanced?
When forces are equal and opposite to each other, they can be said to be balanced as the resultant force is zero.
What are two different categories of forces.
Contact and non-contact forces
What are contact forces?
These are forces that act when an item comes into physical touch with them, i.e muscular forces, friction forces, spring forces
What are Non-contact forces?
These are forces which can act without coming into physical touch with an item i.e gravitational, electromagnetic, electrostatics etc
What is a muscular force?
Muscular force is a contact force in which force is exerted by the muscles of the body.
For example, jumping, kicking, running, walking, climbing, lifting, and pushing all are exerted by our muscles.
What is frictional force?
Frictional Force is a contact force that always opposes the body’s state of motion over another body.
For example, if we stop paddling a bicycle, gradually it gets slows down and stops after covering some distance.
What is magnetic force?
Magnetic force is a non-contact force exerted by a magnet on any other magnetic substance. For example, if we bring a magnet near an iron nail then the magnet pulls them towards it since magnets exert force.
What is electrostatic force?
An electrostatic force is a non-contact force that can be exerted by a charged object on another object from a distance. For example, when a plastic comb is rubbed in dry hair, then the electrically charged comb attracts a tiny piece of papers
What is gravitational force?
The Gravitational force is a non-contact force between two bodies having some mass. It is an attractive force. The force of attraction between the earth and any object is called the force of gravity.
What did galileo use experiments to demonstrate?
Galileo used experiments to demonstrate that when there is no external force acting on an object, it moves at a constant speed.
He could observe that a sphere’s speed rises as it rolls down an inclined plane because of its gravitational attraction on it.
What is the line of action of a force?
The line of action of a force is the path it takes as it exerts its force on an object.
What is the point of application of a force?
the location where it is exerting its force on an object.
What is the force of friction?
The force of friction is the force that opposes the relative motion between the surfaces of two objects in contact and acts along the surfaces
When is the net force of an object 0?
when all the forces are equal and balanced.
When the body is at rest or constant velocity.
A net force acting on a body, however, can change either the magnitude or the direction of its velocity if all of the forces acting on it result in an unbalanced force, which indicates that the unbalanced force can accelerate the body.
For instance, when a body is exposed to a number of forces and is determined to be at rest, we can conclude that there is zero net force operating on the body.
What is newtons’s first law of motion?
A body in the state of rest stays at rest and a body in the state of uniform motion stays at uniform motion until and unless a net external force is applied
we can say that an object which is at rest will continue to stay at rest and an object which is in uniform motion continues to stay in uniform motion until an external force is applied. The first law of motion is also called as Law of Inertia.
What is inertia?
The natural tendency of an object to resist a change in its state of rest or in its state of uniform motion is called Inertia.
What are the two conditions of newton’s first laws?
For Objects at Rest: If an object is at rest, i.e. there, velocity and acceleration are zero. The object will remain at rest until an external force is applied.
For Objects in Motion: If an object is in a state of uniform motion, i.e. it has an initial velocity. The object will remain in a state of uniform motion until an external force is applied.
What is a balanced force?
The force is said to be balanced forces if they nullify one another and their resultant force is equivalent to zero.
What is an unbalanced force?
When two opposite forces acting on a body, move a body in the direction of the greater force or forces which bring a motion in a body are called unbalanced forces.
Examples of newton’s first law?
A roller coaster uses the principle of inertia. It continues to move in the same direction at a constant speed until the tracks act as an external force that changes its direction.
If you slide a hockey puck on ice, eventually it will stop. This is because of friction on the ice or if it hits something, like a player’s stick or a goalpost.
A book lying on the table remains at rest as long as no net force acts on it.
A marathon runner continues to run several meters beyond the finish line due to inertia.
If pulled quickly, a tablecloth can be removed from underneath the dishes. The dishes remain still unless the friction from the movement of the tablecloth is not too high in magnitude.
Men in space find it more difficult to stop moving because of a lack of gravity acting against them.
What is acceleration?
Change of velocity per unit time
What is uniform acceleration?
Where the velocity of an object moving along a straight line changes at a constant rate
