For the work-energy theorem, the work needed to stop the bus is equal to its variation of kinetic energy:
where
W is the work
Kf is the final kinetic energy of the bus
Ki is the initial kinetic energy of the bus
Since the bus comes at rest, its final kinetic energy is zero:
, so the work done by the brakes to stop the bus is
And the work done is negative, because the force applied by the brake is in the opposite direction to that of the bus motion.
I am not as sure but I think it is 9.469 miles
The height attained by the ball is 11.86m
a ball is shot from the ground straight up into the air its initial and final velocity is
initial velocity, u = 50 ft/s = 50×0.305 = 15.25m/s
final velocity ,v = 0 m/s
gravity =-9.8 m/s²
( negative sign shows acceleration in opposite direction)
height =?
using the newton motion of equation
v² = u² + 2as
where
a= acceleration due to gravity(g)
s = height
v² = u² + 2gs
(0)² = (15.25)² + 2×(-9.8)×s
0 = (15.25)² - 19.6 × s
s= - (15.25)²/ 19.6
s = 11.86m
after ignoring the air resistance the maximum height of the ball is 11.86m
To learn more about motion under gravity -
brainly.com/question/27962354
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The sun's source of energy is know as nuclear fusion (means to fuse) this process has a small nuclei atoms that join together to form a large nucleus. The result of this process is released energy. The fusion of hydrogen into helium in the sun makes a large amount of energy and this is known as the sun's energy source.
The theories that scientist proposed about the source of the sun's energy was that the sun burned fuel to generate its energy and that gravity was causing the sun to shrink slowly and have its energy released. Also both of these theories were disproved.
.
Answer:
30°
Explanation:
According to the second law of reflection, it States that the angle of incidence i is equal to the angle of reflection r.
The angle of incidence is known to be the angle between the incident ray and the normal.
The Angle of reflection is the angle between the reflected ray and the normal.
This normal ray is a ray that is perpendicular to the surface.
According to the question, if the beam of light is reflected off the surface and its angle of incidence is 30°, its angle of reflection will also be 30° i.e i=r = 30°
