Physics 1-5 (homework helper)

Applied force

(Fa) is the force being exerted by the student on the des

work

the product of the displacement and the component of the force in the direction of the displacement when the the displacement and force lie along the same angle the formula can be simplified to read W=Fd mass= w=mg d cos 0 (0 theta angle)

Spring constant (k)

the ratio of the force applied to a spring and the distance it is stretched or compressed gives us the proportionality constant (k) which is appropriately called spring constant.

Kinematics

the study of motion of object without regard for the force that influence the object.

Inelastic collision

the total kinetic energy of the system is not conserved. An inelastic collision is sometimes referred to as a "sticky" collision, because the objects remain in contact after the collision.

Tangential speed

there is a convenient formula showing the relationship between angular speed and tangential speed. Tangential speed = distance from axis X angular speed v=rw

formula for velocity

v=√ 2gh

Kinetic friction

when one object is moving relative to the other , this force is called kinetic friction.

Static friction

when the two objects are not moving relative to each other , this force is called --static friction - static mean "unchanging " or "Unmoving"

Coefficient of Kinetic friction

(y)Fn= normal force (Fn=-Ew=-mg) Ff= static friction (Ff=Us Fn) Force of the kinetic friction = Ff=Uk FN (x)Net force = Fnet= Fa + Ff U= (means) meu

field forces

, don't require physical contact to work (includes gravity and magnetism, act over distances .

1-Instantaneous acceleration 2-constant or uniform acceleration

1- acceleration at a particular instant 2- if an object accelerates at a constant rate

Gravity rate- -equations for free fall, with constant acceleration of G

9.81 m/s

resultant force (Fr)

An object may have several different forces acting on it, which can have different strengths and directions. But they can be added together to give the resultant force. This is a single force that has the same effect on the object as all the individual forces acting together.

Formula for calculating the weight of an object on Earth

Fw=mg

formula for the x component of weight

Fwx = mg sin 0 (0 is theta angle )

Gravitational Potential Energy

Gravitational potential energy is the stored energy that an object has due to its own mass and its position above a reference point

kinetic energy

In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes.

Newton's First Law -The Law of Inertia

In the absence of an unbalanced (net) force , an object in motion will remain in uniform motion, and an object at rest will remain at rest

Instantaneous Velocity

Is the velocity that an object has at a particular instant

Projectile

Only force acting upon it is gravity (we ignore air resistance)

energy

The ability to do work. [work and energy are intimately linked. so much so , in fact, hey are both measured in the same units: joules

Newtons second law of motion -the law of acceleration

The acceleration an object experience is directly proportional to the net unbalanced force exerted upon it and inversely proportional to its mass F=ma

Net Force (Fnet)

The vector sum of all the forces acting on an object

Newton's Third Law -The Law of Action-Reaction

When an object exerts a force on a second object, the second object exerts an equal and opposite force on the first object.

field force

a force that act over a distance ex-gravity

acceleration at a angle (x)

a=g sin 0 ( 0 is the theta angle )

elastic collision

both momentum and the kinetic energy are conserved. In other word, the total momentum before the collision is equal to the total momentum after the collision and the total kinetic energy before the collision is equal to the total kinetic energy after the collision.

elastic potensial energy

can be found on springs. When a spring is compressed or stretched , it has the ability to do work i the order to restore itself to its equilibrium position (rest) position.

centripetal Acceleration

centripetal force Fe=ma

Linear momentum

for questions that ask you to calculate the change in the momentum of a single object where the mass of the object does not change, use the following formula ΔP=Pf-Pi=mvf-mvi=m(vf-vi)

(ff) The fricion

force exerted on the desk by the floor in the direction opposite to its motion.

Friction

is a force between two objects that are in contact with each other, exerted parallel to the surface of contact.

Weight

is a measure of the force of gravity between two objects, one of which is usually earth. -If we know the mass of an object, we can determine it's weight in newtons by multiplying its mass by its acceleration. ( your weight change due to location)

Intersia

is an objects resistance to any changes in its motion.

Average velocity

is the average velocity an object travels with over a period of time

(Fn) the normal force

is the force being exerted by the floor on the desk perpendicular to the surface of the floor.

(fw) The weight

is the force exerted by earth on the desk.

Rotational Motion

is the motion of an object around an axis. This differs from translational motion , which we have been studying up until now, in that a rotating object may be in motion around an axis with out showing an overall displacement with reference to a nearby object. A hockey puck sliding across a patch of ice shows translational motion . If the puck is also spinning it has rotational motion as well.

Acceleration

is the rate at which velocity changes

coefficient of friction

is the ratio of the force of static or kinetic friction to the normal force

force

push or pull (something that is capable of changing an object velocity) (vector quantity)

scalar

quantity such as speed or distance, requires that no direction be specified

Displacement

represent a change in object position in a particular direction.

Distance

represents how far an object moves.

Deceleration

slowing down