The name exists because cathode ray devices
predate the discovery of the electron. The sharp
shadows produced by Crookes tubes meant that
something was travelling in a straight line from the
cathode down the tube, so they were named
cathode rays .
1) u= 10m/s
h=1.0m
g =10m/s^2
T= √2h/g
T=√2(1)/10
T=√0.2
T=0.455
V=u+GT
u=0
g=10m/s
T=0.455
V=0+10(0.45)
V=4.5m/s
1b - They are produced by the negative electrode,
or cathode, in an evacuated tube, and travel
towards the anode.
- They travel in straight lines and cast sharp
shadows.
3a In physics, a standing wave – also known as a
stationary wave – is a wave in a medium in which
each point on the axis of the wave has an
associated constant amplitude. The locations at
which the amplitude is minimum are called nodes,
and the locations where the amplitude is
maximum are called antinodes
4a
-They are used in the fields of communications,
4b
-warfare
-in exploring spac
5)-traveling wave tubes
-Hall Effect sensors
-high temperature-resistant permanent
magnets
-thin-film coating equipment
-flywheel storage systems.
9 )Boyle's law state that a law stating that the
pressure of a given mass
of an ideal gas is inversely proportional to its
volume at a constant temperature.
9 bi) Renewable energy is energy generated
from
natural resources—such as sunlight, wind, rain,
tides and geothermal
9bii) rain
wind
Sunlight
Geothermal
12a . decay constant is define as the
instantaneous rate of decay per unit atom of a
substance.
12bii) Control rods are used for maintaining the
desired state of fission reactions within a
nuclear reactor (i.e. subcritical state, critical
state, power changes) They constitute a key
component of an
emergency shutdown system (SCRAM) .
Control rods are rods, plates, or tubes
containing a neutron absorbing material
(material with high absorbtion cross-section for
thermal neutron) such as boron , hafnium,
cadmium , etc., used to control the power of a
nuclear reactor. By absorbing neutrons, a
control rod prevents the
neutrons from causing further fission
10 a)
Sound Waves
1. Require a medium.
2. Travel with a speed of 332 m/s at 0 C.
3. Are longitudinal waves consisting of
compressions and rarefactions.
Light Waves
1. Do not require a medium
2. Travel with a speed of 3 *10 8 m/s.
3. Are electromagnetic waves consisting of
varying electric and magnetic fields.
(12ai) Decay constant is defined as the
instantaneous rate of decay per unit atom of a
substance.
(12aii)
Halflife ,T=0.693/decay contant. Hence, decay
constant,llamda =0.693/T ; =0.693/3days;
=0.182day-1 i.e per day.
(12bi) the moderator of a nuclear fission reactor
is made up of graphite. Its function is that slow
down the movement of a neutron,so that the
chain reaction will not dry out.
(12bii) the control rods is made of Boron
steel.its function is to ensure movement of the
floor,so that it can shut off the reactor
automatically in case of electrical failure
(11a) principle of conservation of linear Momentum states
that in any system of colliding objects the total momentum
is always conserved provided that there is net external
force acting on the system.
(11bi)
Impulse IA = change in momentum of A
= final momentum of A
– initial momentum of A
MAVA – MAVA
Impulse IB = change in momentum of B
= MBVB – (MBUB)
= MBUB
(11ci)
The brightness of the bulb remains the same
since the same current will flow through them
(11cii)
(a)The resistor should be connected in parallel
with the galvanometer
(b)VR=Vg
I*R=0.05I*Rg
IR=0.05I*100
IR=5I
R=5I/I
R=5ohm
(11di)
I=40sin5w(pie)t
but I=Iosin2(pie)ft
therefore 2(pie)ft=500(pie)t
2f=500
f=500/2
f=250Hz
(11dii)
Io=40amp
11diii)
Ir.m.s=Io/sqroot2
=40/sqroot2
Ir.m.s=28.3amp
Or
(5) Applications of permanent magnet:
(i) in telephone earpiece
(ii) in electrical bell
(iii) in generators
(iv) in electrical motors
(v) in induction coil systems
2)-Concentration of electrolyte
-Nature of electrode
-Positions of ions in the electrochemical series
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