Answer:
B electricity could not be distributed through power lines to people's homes
The James Webb Space Telescope (JWST) is a space observatory developed among 20 countries, is being built and operated jointly by NASA, the European Space Agency and the Canadian Space Agency, to be the scientific successor of Hubble and Spitzer. The JWST will offer an unprecedented resolution and sensitivity, some of its main objectives is observe the formation of the first galaxies of the universe and study the formation and evolution of galaxies. The JWST will allow to observe wavelengths within the so-called near-infrared astronomy, but also the orange and red visible light. The importance of this spectrum range is due to the fact that the infrared light can penetrate dusty regions and reveal what is inside. It will be launched in March 2021, the dimensions of its main mirror are 20,197 m × 14,162 m (66.26 ft × 46.46 ft). The JWST will orbit the sun 1.5 million kilometers away from the Earth
For the answer to the question above, i<span>n </span>direct current<span> (</span>DC<span>), the </span>electric charge<span> (</span>current)only flows<span> in one direction. </span>Electric charge<span> in alternating </span>current<span> (AC), on the other hand, changes direction periodically. The voltage in AC circuits also periodically reverses because the </span>current<span> changes direction. So my answer is A.</span>
Answer:
4.7 x 10³ rad / s
Explanation:
During the time light goes and comes back , one slot is replaced by next slot while rotating before the light source
Time taken by light to travel a distance of 2 x 500 m is
= (2 x 500) / 3 x 10⁸
= 3.333 x 10⁻⁶ s .
In this time period, two consecutive slots come before the source of light one after another by rotation. There are 400 slots so time taken to make one rotation
= 3.333 x 10⁻⁶ x 400
= 13.33 x 10⁻⁴ s
This is the time period so
T = 13.33 X 10⁻⁴
Angular speed
= 2π / T
= 
4.7 x 10³ rad / s