GENERAL PHYSICS 1

FORCES

An interaction between two or more objects creates a pair of equal but oppositely directed forces acting on each of the objects

Contact Force

•Friction Force

• Tension Force

• Spring Force

• Applied Force

• Thrust Force

• Drag Force

• Air and Water Resistance

• Normal Force \n • Buoyant Force

Non - Contact Force

• Strong Force \n • Weak Force \n • Electromagnetic Force • Gravitational Force

CONTACT FORCE

Requires physical contact between objects

CONTACT FORCE

is a force that is applied by object

in contact with each other

CONTACT FORCE

acts on the point of direct contact between the two objects

CONTACT FORCE

▷This force can either be continuous as a continuous force or can be momentary in the form of an impulse

CONTACT FORCE

is governed by Newton’s Law. Contact force is responsible for most of the interactions we experience in daily life.

Tension Force

is defined as the force that is transmitted through a rope, string, or wire when pulled by forces acting from opposite sides.

Tension Force

is directed over the length of the wire and pulls energy equally on the bodies at the end

Normal Force

is the force that surface exert to prevent solid object from passing through each other

Normal Force

are always directed perpendicular to the surface

Normal Force

a force experienced by an object lying on the surface; also described as a support force that is always perpendicular to a surface

Frictional Force

refers to the force generated by two surfaces that contacts and slide against each other

Frictional Force

These forces are mainly affected by the surface texture and amount of force impelling them together.

Frictional Force

resists the motion; caused by the interaction between the surfaces in contact, resulting in a resistance to the object’s motion.

Spring Force

is the force exerted by a compressed or stretched spring upon any object that is attached to it.

Spring Force

an object that compresses or stretches a spring is always acted upon by a force that restores the object to its rest or equilibrium position.

Spring Force

experienced by an object linked with the restoring force that aims to return the object to equilibrium; usually associated with compressed or stretched spring or an elastic material.

Thrust Force

is a force or a push. When a system pushes or accelerated mass in one direction, there is a thrust (force) just as large in the opposite direction

Thrust

is used to describe how strong the engines pushes

Thrust Force

a forced experienced by an object whenever fluid is expelled by it (e.g., propeller, turbine, rocket, etc.)

Drag Force

a reaction force that resists the motion of an object in a fluid; the direction of resistance is opposite the motion of the object

Air and Water Resistance

oppositely directed force experienced by an object moving in air (aerodynamic drag) or water (hydrodynamic drag)

Buoyant Force

a force experienced by an object that is partially or wholly submerged in a fluid; equal to the weight of the amount of fluid displaced by the submerged object

non-contact force

is a force applied to an object by another body that is not in direct contact with it.

Non-contact forces

come in play when objects do not have a physical contact between them or when a force is applied without any interaction

Non-contact forces

Also called action-at-a-distance, which arises even without physical contact between the objects and even if the objects are distant from each other.

Gravitational Force

is a force that attracts any two objects with mass

Gravitational Force

• attractive because it always tries to pull masses together, it never pushes them apart.

- it is a force exerted by object with mass

Strong Force

also known as strong nuclear force, it keeps the nucleons and their components (quarks) together and is the strongest of all fundamental forces

quantum chromodynamics

The theory that deals with the idea of a strong force which states that fractionally charged quarks interact by means of particles called “gluons”

Weak Force

often dubbed as weak nuclear force, it is the force responsible for some identified nuclear phenomenon: a form of which beta decay.

electroweak theory

says that W and Z bosons make an interaction between objects possible

Electromagnetic Force

cts between electrically charged particles.

Work

if a force causes an object to move.

Scalar Dot Product

• A product is obviously a result of multiplying 2 numbers. A scalar is a quantity with NO DIRECTION. So basically Work is found by multiplying the Force times the displacement and result is ENERGY, which has no direction associated with it.

Energy

Capacity to do WORK

Gravitational Potential Energy

Energy due to position of an object relative to Earth’s ground

Kinetic Energy

• Energy possessed by a body because of its

  motion

Mechanical Energy \n

The sum of the potential and kinetic energies

of a body

center of mass

is the point located at the object’s average position of mass.

Center of Mass

is a system is the location in space where a force that is applied to the system will make it move without the tendency to rotate

Geometric Center

s the physical center of a system.

MOMENTUM

It is the product of the mass of the object and its velocity

MOMENTUM

“The more mass on a body has, the greater its tendency to stay at rest”

Linear Momentum

s the body to continue in uniform motion along a straight line/path.

Newton’s Law and Momentum

• The change in an object’s momentum divided by the elapsed time equals the constant net force acting on the object

• Newton’s Second Law

• can be used to relate the momentum of an object to the resultant force acting on it.

IMPULSE

When a single, constant force acts on the object, there is an impulse delivered to the object

IMPULSE

The equality is true even if the force is not

constant

IMPULSE

Vector quantity, the direction is the same as the direction of the force

Impulse - Momentum Theorem

The theorem states that the impulse acting on a system is equal to the change in momentum of the system

• Momentum

• is conserved in any collision

• Inelastic Collisions

1. Kinetic energy is not conserved

Perfectly inelastic collisions

occur when the object stick together.

• Elastic collisions

• Both momentum and kinetic energy are

  conserved

• Actual collisions \n

• Most collisions fall between elastic and

  perfectly inelastic collisions

1. non-perfect inelastic collision

1. momentum is conserved but kinetic energy is not. Moreover, the objects do not stick together

1. perfectly inelastic collision

1. momentum is conserved, kinetic energy is not, and the two objects stick together after the collision, so their final velocities are the same.

Momentum

is conserved in all collisions

Mechanical waves

travel through a medium

Mechanical wave

We can describe their movement either through the movement of their particles in the medium and/ or the direction of the wave propagation.

Transverse Waves

Waves are considered as transverse if the direction of the wave propagation is perpendicular to the movement of the medium’s particles.

Longitudinal Waves

Is a wave propagation that is parallel to the direction of the movement of the mediums particles.

Longitudinal Waves

Its waves are characterized by its two region the compressed region (compression) and dispersed region (rarefaction).

Waves on a Liquid

• The particles of water move in a circular manner, while they propagates towards the right.

Waves on a Liquid

• Since the particles movement is not constricted to the horizontal axis, this reveals that the direction of wave motion is neither solely parallel nor perpendicular to the movement of the particles of the medium

1. Periodic Waves

• are generated from repetitive or periodic motion resulting from repeated transverse force exerted on a rope.

• periodic longitudinal wave.

• Another example of periodic wave is that of the_______

1. Wave Speed

• is the distance traveled by a given point on the wave in the given interval of time

1. Wave Speed

• It is the product of wavelength and frequency (f), or the wavelength divided by the wave period ().

Standing Waves on a String

• or stationary wave is a wave with peaks that do not appear displaced.

Standing Waves on a String

• The creation of sinusoidal on a string gets reflected and appears to be immobile.

• superposition principle

• “When two waves meet, they interfere.”

• Constructive Interference

• happens when the resulting waves becomes one of greater amplitude.

• Destructive Interference

• happens when the resulting waves gets a diminished amplitude.

• Node

• refers to a point with minimum displacement from the equilibrium position.

• Antinode

• refers to the point maximum displacement.

Sound wave

is a longitudinal wave. For humans, the audible range is between 20 - 20,000 Hz.

ultrasonic

Sound frequencies that are above this range

infrasonic.

frequencies below this range of sound frequency

Loudness

is the phenomenon of the wave of sound which is dependent on the amplitude of the wave.

Pitch

pitch of sound is primarily determined by the frequency of sound.

High Pitch Sound

Greater Frequency

Low Pitch Sound

Lower Frequency

Timbre (tone color)

the quality of sound and refers to the difference in sound.

Avarage Speed of Sound

In air, the average speed of sound is around 340 m/s. Also note that the speed of sound is dependent on the temperature of the air.

Doppler Effect

When sound source approaches a person, its pitch appears to increase in relation to the ears of that person; then, the sound seems to drop as the source goes aways from the person.

Inertia

is the tendency of an object to resist changes in its velocity: whether in motion or motionless.

• Mass

• is that quantity which solely upon inertia.

LAW OF INERTIA

• A body at rest will remain at rest and a body in motion will continue to move with constant velocity, unless acted upon by unbalanced external force.

LAW OF ACCELERATION

• The greater the force, the greater \n the acceleration. The lesser the force, the lesser the acceleration.

• ⁍  The lesser the mass, the greater the acceleration. The greater the mass, the lesser the acceleration.

acceleration

The ________ of an object is directly proportional to the net force acting on the object and inversely proportional to the mass of the object.

LAW OF INETERACTION

• For every action, there is an equal and opposite reaction.