semester 1 definitions

Question 1

physical quantities

Answer 1

those quantities that can be measured and can be assigned some units
(length - m
mass - kg
time - s
angle - degree
volume - m^3, L, mL)

Question 2

scalars

Answer 2

quantities that can be completely defined by magnitudes only (length, time, speed, temperature)

Question 3

vectors

Answer 3

quantities that can be defined by using both magnitude and direction (force, velocity, acceleration)

Question 4

distance

Answer 4

path taken between 2 points

Question 5

displacement

Answer 5

shortest distance between 2 points

Question 6

speed

Answer 6

change in distance with respect to time (rate of change of distance

Question 7

velocity

Answer 7

rate of change of displacement (how displacement changes with time)

Question 8

acceleration

Answer 8

how velocity changes with respect to time

Question 9

deceleration / retardation

Answer 9

negative acceleration

Question 10

S
U
V
A
T

Answer 10

S - displacement
U - initial speed
V - final speed
A - acceleration
T- time

Question 11

stationary

Answer 11

not moving / not changing

Question 12

s - t graphs

Answer 12

displacement - time graphs

Question 13

v - t graphs

Answer 13

velocity - time graphs

Question 14

force (push or pull)

Answer 14

push or pull on an object that attempts to change its motion, shape, or size

Question 15

inertia

Answer 15

capacity of an object to resist a change in motion from a force

Question 16

momentum

Answer 16

physical ability, stamina in a weight

Question 17

friction occurs?

Answer 17

when 1 object is being pulled or pushed while in contact with another object

Question 18

air resistence

Answer 18

another form of friction that occurs when an object is moving through the air

Question 19

drag force

Answer 19

the opposing force on the object’s moving through fluids

Question 20

terminal velocity

Answer 20

the constant velocity of a falling object when the force of air resistance is equal in magnitude and opposite in direction to the force of gravity (gravity and air resistance is the same)

Question 21

equilibrium

Answer 21

total force = 0, no change in motion, constant speed or rest or bar in a state of balance

Question 22

force (state of motion)

Answer 22

brings change in state of motion in an object

Question 23

moment of a force (description)

Answer 23

rotational effect brought on a body due to application of force

Question 24

moment of a force (definition)

Answer 24

product of the force and the perpendicular distance from the pivot to the line of action of the force

Question 25

principle of moments

Answer 25

if a body is not to rotate, the net clockwise moment of a force on it must equal the net anti clock wise moment of a force

Question 26

center of gravity

Answer 26

the point on a body where the whole of the weight of the object is assumed to be acting

Question 27

energy

Answer 27

the ability of a body to perform work

Question 28

principle of conservation of energy

Answer 28

the total energy of a system always remains constant but it can change from 1 form to another

Question 29

kinetic energy

Answer 29

the energy possessed by moving objects

Question 30

potential energy

Answer 30

the energy possessed by objects due to their position or configuration

Question 31

gravitational potential energy

Answer 31

energy possessed by objects due to their height from the surface of the Earth

Question 32

elastic potential energy

Answer 32

energy possessed by objects due to stretch / energy possessed by strained objects

Question 33

electric potential energy

Answer 33

the energy acquired by the charged particles in electric field (positive and negative attraction

Question 34

power

Answer 34

the rate at which energy is transferred, or the rate at which work is done (how fast work is done)

Question 35

efficiency

Answer 35

how much useful work is done in a given time without wasting much energy