Answer:
More than enough solar energy (8.2 million quad BTUs, 1 quad = 2.9 x1011 kWh) hits Earth's surface each year to meet all of societies' needs. Currently we use about 400 quads per year to run our society. Good building design allows passive use of sunlight to heat homes. Simple solar collectors are used to heat water and cook food. As useful as it is for these purposes, thermal energy from sunlight is still a low quality energy compared to electricity. Computers, most machinery, light bulbs, subway trains, and much more all require electricity. It is possible to turn thermal energy from the sun into electricity. In this unit we will examine how.
. We will also examine how to make electricity directly from light using the photovoltaic cells.
Answer:
David
Explanation:
Because he is not on the ride with Ben and Justine
<h2>The option ( c ) is correct</h2>
Explanation:
When we apply the force on any body , the inertia comes into play . It is the tenancy of the the body to oppose the force which tends to change its state .
In first case the train tries to change its state from rest to motion . Thus the inertia of rest opposes this tendency.
In the second case , the train tries to come from motion to the state of rest . Thus again , inertia opposes it .
Therefore inertia is the factor which creates difficulty in both case . Hence option ( c ) is correct
Period = 1 / frequency
Period = 1 / (35,621 /s)
Period = 2.8073... x 10⁻⁵ sec
Period = <em>28.07 microseconds</em>
or
Period = <em>0.0281 millisecond</em>
