Answer:
Explanation:
Energy of signal being radiated per second on all sides = 71 x 10³ J .
At a distance of 220 m it is spread over an area of 4 π x (220)² because it is spreading uniformly on all sides.
So energy crossing per unit area
= 
= 11.67 x 10⁻² Wm⁻²s⁻¹.
This is the intensity of the signal.
At 2200 m this intensity will further reduce by 100 times
So there it becomes equal to
11.67 x 10⁻⁴ Wm⁻² s⁻¹.
Rachel Carson was the author of the acclaimed environmental book, Silent Spring. The book was published in 1962.
It documented the negative effect that synthetic pesticides have on the environment, specifically on birds.
This book laid bare to the American public what chemical companies indirectly contributed to the environment.
The public furor this book caused led to the reversal of the national pesticide policy, a nationwide ban on DDT for agricultural uses, and inspired the creation of the U.S. Environmental Protection Agency.
Answer:
a) B=0.008 T
b) +z direction
Explanation:
<u>solution:</u>
a) The magnetic force:
F=i*l*B
Solve for B:
B=0.008 T
b) According to the left hand rule, the magnetic field is in the +z direction
Answer:
a = √ (a_t² + a_c²)
a_t = dv / dt
, a_c = v² / r
Explanation:
In a two-dimensional movement, the acceleration can have two components, one in each axis of the movement, so the acceleration can be written as the components of the acceleration in each axis.
a = aₓ i ^ + a_y j ^
Another very common way of expressing acceleration is by creating a reference system with a parallel axis and a perpendicular axis. The axis called parallel is in the radial direction and the perpendicular axis is perpendicular to the movement, therefore the acceleration remains
a = √ (a_t² + a_c²)
where the tangential acceleration is
a_t = dv / dt
the centripetal acceleration is
a_c = v² / r
