Lecture 3: Kinematics and Dynamics

Scalar

vô hướng: quantities that have magnitude only.

magnitude

độ lớn

Vectors

quantities that have direction as well as magnitude

co-planar vectors

vectơ đồng phẳng: vectors that lie in the same plane.

distance

khoảng cách: the length of the path taken, a scalar quantity

displacement,

độ dịch chuyển: the straight-line distance and the direction from a fixed point, a vector

quantity.

speed

tốc độ: the distance travelled per unit time. Its SI unit is meter per second (ms-1).

velocity

vận tốc: the rate of change of displacement.

acceleration

gia tốc: the rate of the change of velocity. Its magnitude is given by the slope or gradient of a (v-t) graph.

gradient

slope, độ dốc

constant acceleration

is a straight-line

free falling

rơi tự do: the resistive force acting on a body moving through air. Its direction is always opposite to the direction of motion. Its magnitude depends on the speed and cross-section area of the body, and the density of the air.

density

mật độ

resistive force

lực cản

trajectory

quỹ đạo: due to uniform velocity in one direction and an uniform acceleration in a perpendicular direction, is a curve called parabola

equilibrium

sự cân bằng: A situation in which the forces acting upon an object are in balance.

Law1: A body remains at rest or continue to move in a straight-line with a uniform velocity unless a net force acts on it.

Law2: The rate of change of momentum of a body is proportional to the net force

producing it and takes place in the direction of this net force.

Law3 : The forces of action and anti-action between interacting bodies are

equal in magnitude, opposite in direction and act on different bodies.

inertia

quán tính: the resistance to acceleration upon the application of a force. The mass of a

body is a measure of its inertia. Its SI unit is the kilogram.(kg)

weight

trọng lượng: the effect of a gravitational field on a mass.

linear momentum

động lượng tuyến tính: as the product of its mass and its velocity.

Force

lực: the rate of change of linear momentum

hooke’s law

ĐL về độ đàn hồi: within its elastic limit, the magnitude of the tension in an elastic body is directly proportional to its extension.

elastic

độ đàn hồi

tension

lực căng

extension

độ giãn

gravitational field

trường hấp dẫn: due to a mass is a region of space within which a gravitational force is

experienced by another mass.

electric field

trường điện: due to charge is a region of a space within which an electric force is experienced by another charge.

pressure

áp suất, áp lực: defined as the force per unit area.

up thrust

lực đẩy lên: the upward (or buoyant) force exerted by a fluid on a body when the body is

(completely or partially) immersed in the fluid.

buoyant

=upward force

frictional forces

lực ma sát: resist the relative motion between the two solid surfaces in contact. They are

always opposite in the direction to motion or the tendency to move.

resist

chống lại

viscous force

lực nhớt: a fluid resist the relative motion of a body through the fluid.

Resonance

Hiện tượng cộng hưởng

suspension

sự treo

concrete

bê tông

amplitude

biên độ

disaster

thảm hoạ

instantaneous

tức thời

angular momentum

momen động lượng

consistency

sự nhất quán

copernicanism

thuyết nhật tâm

geocentrism

thuyết địa tâm

telescope

kính thiên văn