Every practical source of energy that you can imagine, as well as a few impractical ones, are used somewhere in the USA.
From whale oil in Alaska, to nuclear energy, to coal, petroleum, natural gas, solar energy, wind energy, and biomass.
Oh ! Geothermal energy and tidal energy aren't too popular, but I'll bet if you looked, you'd find these used too, SOMEwhere in the 50 states.
"Gamma rays" is the name that we call the shortest of all electromagnetic waves. They're shorter than radio waves, microwaves, infrared waves, heat waves, visible light waves, ultraviolet waves, and X-rays. They extend all the way down to waves that are as short as the distance across an atom.
Being so short, they carry lots of energy. They can penetrate many materials, and they can damage living cells and DNA. They're dangerous.
The sun puts out a lot of gamma radiation. The atmosphere (air) filters out a lot of it, otherwise there couldn't even be any life on Earth.
As soon as astronauts fly out of the atmosphere, they need a lot of shielding from gamma rays.
You know the precautions we take when we're around X-rays. The same precautions apply around gamma rays, only a lot more so.
It's only in the past several years that we've learned how to MAKE gamma rays without blowing things up. Also, how to control them, and how to use them for medical and industrial applications.
Answer:
The required angle is (90-25)° = 65°
Explanation:
The given motion is an example of projectile motion.
Let 'v' be the initial velocity and '∅' be the angle of projection.
Let 't' be the time taken for complete motion.
Let 'g' be the acceleration due to gravity
Taking components of velocity in horizontal(x) and vertical(y) direction.
= v cos(∅)
= v sin(∅)
We know that for a projectile motion,
t =
Since there is no force acting on the golf ball in horizonal direction.
Total distance(d) covered in horizontal direction is -
d = ×t = vcos(∅)× = 
.
If the golf ball has to travel the same distance 'd' for same initital velocity v = 23m/s , then the above equation should have 2 solutions of initial angle 'α' and 'β' such that -
α +β = 90° as-
d = 
= ![\frac{v^{2}sin(2[90-β]) }{g}](https://tex.z-dn.net/?f=%5Cfrac%7Bv%5E%7B2%7Dsin%282%5B90-%CE%B2%5D%29%20%7D%7Bg%7D)
=
= 
.
∴ For the initial angles 'α' or 'β' , total horizontal distance 'd' travelled remains the same.
∴ If α = 25° , then
β = 90-25 = 65°
∴ The required angle is 65°.
Answer:
F = 878.9 N
Explanation:
The electrostatic force of attraction or repulsion is given by Coulomb's Law as follows:
F = kq₁q₂/r²
where,
F = Force pf repulsion between balloons = ?
k = Coulomb's Constant = 9 x 10⁹ N.m²/C²
q₁ = q₂ = magnitudes of 1st and 2nd charge = 0.0025 C
r = distance between balloons = 8 m
Therefore,
F = (9 x 10⁹ N.m²/C²)(0.0025 C)(0.0025 C)/(8 m)²
<u>F = 878.9 N</u>
Answer:
A
Explanation:
sound waves hit the canyon walls, then bounce back towards you. That's why you hear an echo
