Answer:
A first-class lever: fulcrum is between input and output force; second-class lever: output force is between input force and fulcrum; third-class lever: input force is between fulcrum and output force
Answer:
option 4
Explanation:
Light's velocity in air ( 3 × 10^8 m/s ) is much greater than sound's velocity in air ( 343 m/s )
Hence due to difference in velocities , during lightning light is seen first & sound is heard later
Answer:
<span>GPE=81000J or 81kJ</span>
Explanation
Potential Energy = mgh = 20 x 9.8 x ?
<span>To find H use one of the equation of motion </span>
<span>= [(90)^2 - 0 ] / 2(9.8) </span>
<span>Potential Energy = mgh = 20 x 9.8 x 8100 /2(9.8) = 81000 J</span>
The wavelength of a microwave of 3 x 10^9 Hz frequency is 0.1 m.
The wavelength of a microwave of 3 x 10^9 Hz frequency is calculated using the equation λ = c/f, where λ is the wavelength, c is the speed of light, and f is the frequency.
The speed of light is approximately 3 x 10^8 m/s. Therefore, the wavelength of a microwave of 3 x 10^9 Hz frequency can be calculated as follows:
λ = 3 x 10^8 m/s/3 x 10^9 Hz
= 0.1 m.
Therefore,the wavelength of a microwave of 3 x 10^9 Hz frequency is 0.1 m.
Microwaves are electromagnetic waves that have a frequency between 300 MHz to 300 GHz and a wavelength from 1 mm to 1 m. Microwaves have a variety of uses, including communications, radar, and cooking. Microwave radiation is absorbed by water, fats, and sugars, which is why it is used for cooking.
The frequency of a microwave is usually expressed in megahertz (MHz) or gigahertz (GHz). One megahertz is equal to one million hertz and one gigahertz is equal to one billion hertz. The frequency of a microwave determines its wavelength; the higher the frequency, the shorter the wavelength.
Learn more about electromagnetic waves at :brainly.com/question/3101711
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