Science 9: Impulse and Momentum

Momentum

It is the measure of object’s inertia in motion. It also tells how difficult it is to stop a moving object.

mass and velocity

Its product is equivalent to the momentum of a moving object.

kg times m/s

SI Unit of Momentum

p = mv

What is the formula of momentum?

Velocity

The direction of momentum is defined by the direction of the object’s ___.

p

It is used to represent the momentum of an object.

m

It is used to represent the mass of the object.

v

It is used to represent the velocity of an object.

large mass

A bus can have a large momentum even if it is moving very slowly, because it has a ___.

high velocity

A bullet can have a large momentum even if it has a small mass, because it is moving at a ___.

at rest

If an object is ___ it has no momentum no matter how large its mass.

Impulse

The term ∑F ⃗Δt is known as ___.

vector quantity

What kind of quantity are impulse and momentum?

rate of change in an object’s momentum

The net force acting on an object is equal to the ___ over time.

N times s or kg times m/s

SI Unit for impulse.

Impulse-Momentum Theorem

This states that the change in the momentum of an object during a given time interval equals the impulse of the net force that acts on the object during the given time interval.

product of the summation of the force vector and the change in time

Impulse can be computed using:

summation

What is this symbol read as: ∑?

Force vector

What does this symbol indicate: F⃗ ?

Change in Time

What does this symbol represent: Δt?

Impulse-Momentum Theorem

What is this equation known as: I ⃗=Δp ⃗?

Increasing Momentum

in order to do this, you must increase the magnitude of force and increase the time of contact on object.

Conservation of Momentum

The law states that the momentum of the system is conserved. This implies that the initial momentum of the system is the same as the final momentum.

Conservation of Momentum

What is this formula known as: m_1v ⃗_1+m_2v ⃗_2= m_1v ⃗_1+m_2v ⃗_2

?

Collision

It also shows one of the fundamental laws in physics – the law of conservation of momentum.

Elastic Collisions

It occurs when objects strike each other and no deformation occurs. Kinetic energy and momentum is conserved.

Elastic

A good example of this is seen between billiard ball collisions.

Inelastic collisions

It occurs when objects strike each other and stick together. Momentum is conserved, but kinetic energy is not conserved since deformation occurs between the objects and energy is lost in this process.