Coal is burned to get energy. By burning coal, green houses gases like carbon dioxide, nitrogen oxides and suphur oxides are produced.
Rest of the energy sources given in the option are clean energies.
Answer is A.
Answer: The height above the release point is 2.96 meters.
Explanation:
The acceleration of the ball is the gravitational acceleration in the y axis.
A = (0, -9.8m/s^)
For the velocity we can integrate over time and get:
V(t) = (9.20m/s*cos(69°), -9.8m/s^2*t + 9.20m/s^2*sin(69°))
for the position we can integrate it again over time, but this time we do not have any integration constant because the initial position of the ball will be (0,0)
P(t) = (9.20*cos(69°)*t, -4.9m/s^2*t^2 + 9.20m/s^2*sin(69°)*t)
now, the time at wich the horizontal displacement is 4.22 m will be:
4.22m = 9.20*cos(69°)*t
t = (4.22/ 9.20*cos(69°)) = 1.28s
Now we evaluate the y-position in this time:
h = -4.9m/s^2*(1.28s)^2 + 9.20m/s^2*sin(69°)*1.28s = 2.96m
The height above the release point is 2.96 meters.
Your Question:
<span>A
star is born when gas and dust from a nebula become so dense and hot
that nuclear fusion starts. Which of the following forces is responsible
for the formation of a star?
A.
friction
B.
gravitation
C.
magnetism
D.
electromagnetic energy</span>
Our Teams Answer: B. Gravitation
Our Teams aim's to please and We are happy to help! Its the answer is wrong please notify us quickly for we can fix it quickly! Thanks :)
-ExperimentsDIY
Potential energy = mgh
= 53.5 x 9.8 x 4.7
= 2464.21 Joules
