SCI 403

Physics

SCI 403

100問 • 1年前Physics

問題一覧

is one that has nothing to do with a special direction. many physical concept such as length time temperature mass density charge and volume are scalars; each has a scale or size but no associated direction.

scalar quantity

is one that has be specified completely only if we provide both its magnitude (size) and direction. many physical concepts such as displacement velocity acceleration force and momentum are vector quantities.

vector quantity

or sun of a number of vectors of a particular type is that single vector that would have the same effect as all the original vectors taken together

resultant

this method for finding the resultant of a several vectors consists in beginning at any convenient point and drawing each vector arrow in turn in they may be taken in any order of succession the tail end of each arrow is position at the tip end of the proceeding one

graphical addition of vectors

are defined in the relation to a right angle.

trigonometric function

it is effective value in a given direction. for example the x component of a displacement is the displacement parallel to the x-axis caused by the given displacement.

component of a vector

each vector is dissolved into x -, y -, nc components, with negatively directed components taken as negative

component method

have a magnitude of 1 and are represented by the bold face symbol top with a caret

unit vectors

when an object moves from one point in space to another the displacement is the vector from the initial location to the final location. it is independent of the actual distance travel

displacement

is a scalar quantity. if an object takes a time interval t to travel a distance l, then average speed equals total distance travel over time taken

speed

is a vector quantity. if an object undergoes a vector displacement s in a time interval t then average velocity equals vector displacement over time taken

velocity

measures the time rate of a change of velocity average acceleration=change in velocity vectors/time taken

acceleration

is a constant and lies along the line of displacement vector

acceleration vector

either the direction may be chosen as positive. if a displacement velocity or acceleration is in the opposite direction. it must be taken as _____________.

negative

is the average velocity evaluated for a time interval that approaches zero

instantaneous velocity

it is an object at a certain time is the slope of a velocity versus time graph at that time

instantaneous acceleration

the acceleration of a body moving only under the force of gravity, which is directed vertically downward

gravitational

the _________ of an object is measure of the inertia of the object

mass

is the tendency of a body at rest to remain at rest, end of a body in motion to continue moving with unchanged velocity

inertia

is an object whose mass is defined to be 1 kg. the masses of other object are found by comparison with this mass. a gram mass is equivalent to exactly 0.001 kg

standard kilogram

is the agency of change. in mechanics it is that which changes the velocity of an object. it is a vector quantity having magnitude and direction

force

is one whose source lies outside of the system being considered

external force

acting on an object causes the object to accelerate in the direction of that force

net external force

an object at rest will remain at rest; an object in motion will continue in motion with constant velocity, except in so far as it's acted upon by an external force.

newton's first law

as stated by newton, it was framed in terms of the concept of momentum.

newton's second law

it is a newton's law that matter interact with matter--forces come in pairs. this is often called the law of action and reaction

newton's third law

when two masses m and m' gravitationally interact, they interact each other with forces of equal magnitude. for point masses or spherically symmetric bodies, the attractive force Fg is given by FG=G mm'/r²

law of universal gravitation

is the gravitational force acting downward on the object. on the earth it is gravitational force exerted on the object by the planet. its unit are newtons in the SI and pounds in the british system

weight

falling freely toward the earth's in subject to only one force

mass

acting on a string or chain or tendon is the applied force tending to stretch it.

tensile force

the magnitude of the tensile force

tension

is a tangential force acting on an object that opposes the sliding of the object on adjacent surface with which it in contact. it is parallel to the surface and opposite to the direction of the motion or of impending motion

friction force

on an object that is being supported by the surface is the component of the supporting force that is perpendicular to the surface

normal force

is defined for the case in which one surface is sliding across another at constant speed

coefficient of kinetic friction

is defined for the case in which one surface is just on the verge of sliding across another surface

coefficient of static friction

are forces whose lines of action all pass through a common point. the forces acting on it point object because they all pass through the same point, the point object.

concurrent forces

under the action of concurrent forces provide it is not accelerating

equilibrium

is essentially the force with which gravity pulls downward upon it

weight

about an axis, due to a force, is a measure of the effectiveness of the force in producing rotation about that axis.

torque

what is the units of torque

newtons-meters

a torque that tends to cause counterclockwise rotation about the axis is

positive

the torque the tense to cause clockwise rotation about the axis is

negative

is the point at which the entire weight of the object may be considered concentrated

center of gravity

done by a force is defined as the product of that force times the parallel distance over which it acts.

work

the si unit of work

newton-meter

is a measure of the change imparted to a system. it is given to an object when a force does work on the object

energy

is the energy possessed by an object because it is in motion. if an object of mass m is moving with a speed v, it has translational KE

kinetic energy

is the energy possessed by an object because of the gravitational interaction

gravitational potential energy

it can neither be created nor destroyed, but only transform from one kind to another

energy

is the time rate of doing work or the rate of transfer of energy

power

what is the si unit of power

watt

is the product of its mass and velocity

linear momentum

is a vector quantity whose direction is that of the velocity. the unit are kg•m/s

momentum

is the product of a force and the time interval over which the force acts

impulse

is one in which the sum of the translational KEs of the object is not changed during the collision

perfectly elastic collision

for any collision between two bodies in which the body's move only along a single straight line

coefficient of restitution

is usually expressed in radians, in degrees, or in revolutions

angular displacement

whose axis of rotation is fixed is the rate at which its angular coordinate, the angular displacement, changes with time

angular speed

whose axis of rotation is fixed in the rate at which its angular speed changes with time

angular acceleration

a point mass m moving with constant speed v around a circle of radius is undergoing acceleration. although the magnitude of its linear velocity is not changing, the direction of the velocity is continually changing

centripetal acceleration

is the force that must act on a mass moving in circular path of radius to give it the centripetal acceleration

centripetal force

is a measure of the rotational inertia of the body. if an object that is free to rotate about an axis is difficult to set into rotation

moment of inertia

acting on a body of moment of inertia, produces in it an angular acceleration

torque and angular acceleration

done on a rotating body during an angular displacement by a constant torque is even by W= torque(teta)

work

transmitted to a body by a torque is given by P=(torque)(angular speed)

power

is a vector quantity that has magnitude and is directed along the axis of rotation

angular momentum

has a magnitude torque times time worthy is the time during which the constant torque acts on the object

angular impulse

the moment of inertia of a body about an axis parallel to an axis through the center of a mass

parallel-axis theorem

p of a material it is mass per unit volume

mass density

the si unit of mass density

kg/m³

is the ratio of the density of the substance to the density of some standard substance. It is usually water (4°C) for liquids and solids while for gases, it is usually air

specific gravity

is the property by which of body returns to its original size and shape when the forces that deform it are removed

elasticity

experience within a solid is the magnitude of the force acting, divided by the area over which it acts

stress

what is the si unit for stress

pascal

is the fractional deformation resulting from a stress. it is measured as the ratio of the change in some dimension of the body to the original dimension in which the change occurred

strain

is the smallest stress that will produce a permanent distortion in the body. when a stress in excess of this limit is applied, the body will not return exactly to its original state after the stress is removed

elastic limit

is the modulus of elasticity

young's modulus

describe the volume elasticity of a material. suppose that i uniformly distributed comprehensive force acts on the surface of an object and is directed perpendicular to the surface at all points

bulk modulus

what is the si unit of pressure

Pascal

describe the shape elasticity of a material.

shear modulus

what is the standard atmospheric pressure

1.01×10⁵ Pa

due to a column of fluid of height and mass density

hydrostatic pressure

when the pressure on any part of a confined fluid liquid or gas is changed, the pressure and every other part of the fluid is also changed by the same amount

pascal's principle

a body woolly or partly immerse in a fluid is buoyed up by a force equal to the weight of the fluid it deplays. it can be considered to act vertically upward through the center of the gravity of the displace fluid

archimedes' principle

when a fluid that fills in a pipe flows through the pipe with an average speed

flow or discharge

is the rate at which the shares train within the fluid is changing

shear rate

it is a fluid that measure of how large a shear stress is required to produce unit shear rate

viscosity

the fluid flow through a cylindrical pipe of length and cross sectional radius is given by

poiseuille's law

for the study flow of a continuous stream of fluid: considered two different points along the stream path

bernoulli's equation

suppose that attack contains liquid and is open to the atmosphere at its top

torricelli's theorem

is a dimensionless number that applies to a fluid of viscosity and density flowing with speed through a pipe with diameter

reynolds number

maybe measured on the celsius scale, on which the freezing point of water is 0° c, and the boiling point is at 100° c

temperature

scale is displaced 273.15 celsius

kelvin

is the random kinetic energy of the particles (usually electrons ions atoms and molecules) composing a system

thermal energy

is a thermal energy in transit from a system at one temperature to a system that is in contact with it, but is at lower temperature

heat

is the quantity of heat required to change the temperature of unit mass of the substance by 1°

specific heat

in electricity exist in a region when a net electric charge is transported from one point to another in that region

current

is a source of electrical energy

battery

it is from a wire or other object is measure of the potential difference that must be impressed across the object to cause a current of 1 ampere to flow through it

resistance

100

originally contain two parts. it's first part was simply the defining equation for resistance V = IR.

ohm's law

BIO

JOHN ROVINCE MACATANGAY · 25問 · 1年前

BIO