All electromagnetic waves travel in vacuum (space) at the speed of light (3 * 10^8 m/s). Radio waves is just a member of the electromagnetic spectrum. All electromagnetic waves follow the wave equation: speed = frequency * wavelength. With all electromagnetic waves, the speed in space is the same.
1.1 A. An electric oven with a resistance of 201Ω and a voltage of 220V drwa a current of 1.1 A.
The easiest way to solve this problem is using the Ohm's Law I = V/R.
An electric oven has R = 201Ω, and a drop of voltage V = 220v, solve using I = V/R:
I = 220V / 201Ω
I = 1.09 A ≅ 1.1 A
Answer:
Explanation:
Magnets are of two major forms namely the permanent magnet and the temporary magnets. Temporary magnets magnetizes and demagnetize easily while permanent magnets does not magnetizes and demagnetize easily.
This permanents magnets are applicable in loudspeakers, generators, induction motor etc.
To increase the
The following will tend to increase the magnetic force acting on the rotor in an induction motor.
1. Increasing the strength of the bar magnet. Increase in strength of the magnet will lead to increase in the magnetic force acting on the rotor.
2. Increase in the magnetic line of force also known as the magnetic flux around the magnet will also increase the magnetic force acting on the rotor.
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Answer: a.The mirrors and eyepiece of a large telescope are spring-loaded to allow them to return quickly to a known position. </h2>
Explanation:
Adaptive optics is a method used in several astronomical observatories to counteract in real time the effects of the Earth's atmosphere on the formation of astronomical images.
This is done through the insertion into the optical path of the telescope of sophisticated deformable mirrors supported by a set of computationally controlled actuators. Thus obtaining clear images despite the effects of atmospheric turbulence that cause the unwanted distortion.
It should be noted that with this technique it is also necessary to have a moderately bright reference star that is very close to the object to be observed and studied. However, it is not always possible to find such stars, so a powerful laser beam is used to point towards the Earth's upper atmosphere and create artificial stars.
Answer:
c. 307 nm
Explanation:
angular position of first dark fringe = λ / d , λ is wavelength and d is width of slit .
(40 x π ) / 180 = 410 / d
angular position of second dark fringe = 2 x λ / d , λ is wavelength and d is width of slit .
(60 x π ) / 180 = 2 x λ / d
Dividing these equations
60 / 40 = 2 x λ / 410
λ = 307.5 nm.
