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Question 1

define scalar quantity

Answer 1

A scalar quantity is defined as the physical quantity with only magnitude and no direction

Question 2

define vector quantity

Answer 2

A vector quantity is any quantity that has magnitude and direction, such as displacement or velocity.

Question 3

example of a scalar quantity

Answer 3

energy, mass

Question 4

example of a vector quantity

Answer 4

-force, eg 20 newtons (N) to the left.
displacement, eg 50 kilometres (km) east.

-velocity, eg 11 metres per second (m/s) upwards.

-acceleration, eg 9.8 metres per second squared (m/s²) downwards.

-momentum, eg 250 kilogram metres per second (kg m/s) south west.

Question 5

g = 9.81

Question 6

linear

Answer 6

graph is straight

Question 7

non linear

Answer 7

Non-linear means the graph is not a straight line

Question 8

suggest why a filament lamp is most likely to fail when first switched on

Answer 8

Bulbs typically break in the first few seconds of usage because the initial current that flows after the bulb is switched on when it is still cold (the ‘inrush current’) is as much as 10 times the magnitude of normal operating currents.

Question 9

units is a volt

Answer 9

joule per coulomb

Question 10

AC, definition and eg

Answer 10

Alternating Current (AC) is a type of electrical current, in which the direction of the flow of electrons switches back and forth at regular intervals or cycles. Current flowing in power lines and normal household electricity that comes from a wall outlet is alternating current.

Question 11

DC, definition and eg

Answer 11

Direct current (DC) is electrical current which flows consistently in one direction. The current that flows in a flashlight or another appliance running on batteries is direct current.

Question 12

insulated wire

Answer 12

coated with a non-conductive material that is resistant to an electric current, which surrounds and protects the wire and cable inside.

Question 13

5A fuse

Answer 13

the fuse melts above a current of 5 A

Question 14

double insulated

Answer 14

Double or reinforced insulation is another method of protection against electric shock,

Question 15

convection current

Answer 15

Air close to the radiator is heated.
It expands, becomes less dense and rises.
It is replaced by the cooler, denser air which surrounds it.
This air is in turn heated, expands becomes less dense and rises.
The process continues, a convection current is set up and heat is transferred through the air and hence through the room.

Question 16

ureka can

Question 17

conduction in non metals

Answer 17

Some of the
electrons
in a piece of metal can leave their atoms and move about in the metal as free electrons.

The parts of the metal atoms left behind are now positively charged metal
ions
.

When the free electrons absorb heat energy, they move much faster.

As they move through the metal, free electrons crash into metal ions.

Some of the
kinetic energy
of the free electron is absorbed by the ions and it vibrates faster and with greater amplitude.

This process is very much faster than conduction caused by just passing vibrations from atom to atom.

Hence, conduction in metals is faster than in non-metals.