<span>ripple factor can be reduced by increasing the value of the load resistor (which means reducing the load of the circuit)</span>
Your answer is electricity, light and magnetism. They can be determined usinf elecromagnetic radioation.
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Even the energy can't be detected by our eyes, there are a lot of measurement instruments that can measure infrared (IR), gamma rays, radio or X-rays or ultraviolet (UV)</span>
The hotter star will be 16 times more luminous - luminosity depends on two things - the size of the star and the temperature of the star. The hotter a star is, the more energy it will give out. This will give rise to greater luminosity.
knowledge of first aid ... eg St John Ambulance, Red Cross etc. I think that everyone in a school should be taught First Aid.
