Answer:
Correct answer: Kinetic energy of rotation, kinetic energy of translation and potential energy
Explanation:
Before it began to rotate it possessed potential energy. After being released from the rest it starts to roll on the roof and get kinetic energy of rotation, kinetic energy of translation along with potential energy.
God is with you!!!
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:
461.88 N
Explanation:
Let tension in each vine be T .
The vertical component of this tension of both the vine will add up and balance the weight .
2T cos 30 = mg
2 T x cos 30 = 800
T = 800 / (2 x cos30 )
= 461.88 N
Answer:
v = 2 v₀
Explanation:
For this exercise we will use the relationship between work and the change in kinetic energy
W = ΔK
Where the work is of the friction force, which is always opposed to the movement whereby the angle is 180º
W = - fr x
The distance for the first case is
x = 1/4 L
We substitute
-fr ¼ L = ½ m v₀²
fr L = 2 m v₀²
In the second case, the new speed takes the ball the entire distance
x = d
-fr L = ½ m v²
We equal the two equations
2 m v₀² = ½ m v²
v² = 4 v₀²
v = 2 v₀
