Ok ok ok ok ok ok I ok ok I I’m only on kn knkkkm I’m on
<u>#2</u>
Use the formula ... Kinetic energy = (1/2) x (mass) x (speed)²
<u>#3 - a).</u>
sun => energy travels as electromagnetic waves => reaches Earth as
heat & light energy.
sun => absorbed in plants => eaten by animals => animals die =>
decay into oil in millions of years => we burn the oil to get the energy.
<u>#3 - b).</u>
food I ate for lunch => metabolized into glucose by my body
=> some of it burned in my muscles to generate energy for immediate needs
=> the rest of it stored as fat for future needs.
<u>#3 - c).</u>
flower pot rolls off the ledge => gravity does work on it all the way down,
producing the kinetic energy it has when it hits the floor.
<u>#3 - d).</u>
oil or natural gas is burned, releasing heat energy => energy is used
to generate electricity => electricity flows through cables from the
power generating plant to your home => hot plate plugged into the
wall => turns electrical energy back into heat energy => heat energy
is conducted into the bottom of the beaker, flows through the glass
to the inside surface => heat energy is conducted from the inside of
the glass to the water, which gets hotter as it absorbs more energy.
=============================
<u>Note:</u>
#1 on the sheet is wrong.
"Work = force x distance" that's correct
But 25-kg is the <em>mass</em> of the ball, <em>not </em>the gravitational <em>force </em>on it.
The force on it is (mass) x (gravity), called its "weight".
That's (25-kg) x (9.8 m/s²) = 245 kg-m/s² = 245 newtons .
Answer:
a) r = 4.22 10⁷ m, b) v = 3.07 10³ m / s and c) a = 0.224 m / s²
Explanation:
a) For this exercise we will use Newton's second law where acceleration is centripetal and force is gravitational force
F = m a
a = v² / r
F = G m M / r²
G m M / r² = m v² / r
G M / r = v²
The squared velocity is a scalar and this value is constant, so let's use the uniform motion relationships
v = d / t
As the orbit is circular the distance is the length of the circle in 24 h time
d = 2π r
t = 24 h (3600 s / 1 h) = 86400 s
Let's replace
G M / r = (2π r / t)²
G M = 4 π² r³ / t²
r = ∛(G M t² / (4π²)
r = ∛( 6.67 10⁻¹¹ 5.98 10²⁴ 86400² / (4π²)) = ∛( 75.4 10²¹)
r = 4.22 10⁷ m
b) the speed module is
v = √G M / r
v = √(6.67 10⁻¹¹ 5.98 10²⁴/ 4.22 10⁷
v = 3.07 10³ m / s
c) the acceleration is
a = G M / r²
a = 6.67 10⁻¹¹ 5.98 10²⁴ / (4.22 10⁷)²
a = 0.224 m / s²
E S *
The "E" represents Earth, "S" represent Sun, and the "*" represents the nearest star(which is Proxima Centauri).
The main thing to worry about here is units, so ill label everything out.
D'e,s'(Distance between earth and sun) = .<span>00001581 light years
D'e,*'(Distance between earth and Proxima) = </span><span>4.243 light years
Now this is where it gets fun, we need to put all the light years into centimeters.(theres alot)
In one light year, there are </span>9.461 * 10^17 centimeters.(the * in this case means multiplication) or 946,100,000,000,000,000 centimeters.
To convert we multiply the light years we found by the big number.
D'e,s'(Distance between earth and sun) = 1.496 * 10^13 centimeters<span>
D'e,*'(Distance between earth and Proxima) = </span><span>4.014 * 10^18 centimeters
</span>
Now we scale things down, we treat 1.496 * 10^13 centimeters as a SINGLE centimeter, because that's the distance between the earth and the sun. So all we have to do is divide (4.014 * 10^18 ) by (<span>1.496 * 10^13 ).
Why? because that how proportions work.
As a result, you get a mere 268335.7 centimeters.
To put that into perspective, that's only about 1.7 miles
A lot of my numbers came from google, so they are estimations and are not perfect, but its hard to be on really large scales.</span>
Answer:
<h2>index of refraction = 1.69</h2><h2>percentage error = 10.58%</h2>
Explanation:
According to Snell's law, the ratio of the sine of angle of incidence to the sine of angle of refraction is a constant for a given pair of media. The constant is known as the refractive index.
Mathematically 
i = angle of incidence measured = 63.5°
r = angle of refraction measured = 32°
n = refractive index
The index fraction calculated is approx. 1.69.
If the index of refraction of a clear plastic as listed in the book is 1.89 and the calculated is 1.69, the percentage error will be calculated as thus;
%error = 
%error = 
%error = 
%error = 10.58%
