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.
Explanation:
We need to find the value of following expression :

Firstly, solving the numerator of the above expression :

Rounding off the result = 9.78
In scientific notation : 
The value of a = 9.78 and k = 0.
Answer: a = 0.35 m/s²
Explanation:
F = ma
a = F/m = 450/1300 = 0.346153... ≈ 0.35 m/s²
Answer:
The amount of air resistance an object experiences depends on its speed, its cross-sectional area, its shape and the density of the air.
Explanation:
Answer:
On a roller coaster, energy changes from potential to kinetic energy and back again many times over the course of a ride. Kinetic energy is energy that an object has as a result of its motion. Traditionally, the coaster cars are pulled up the first hill by a chain; as the cars climb, they gain potential energy.