I believe the answer is A.
Since the Earth is in the Milky Way and not outside it, we cannot see the exact shape of it. Physicists have been able to track and graph the movements of the planets accurately for thousands of years, but that does not mean we know the shape of the entire solar system.<span />
Answer:
<h2>
<em>6,142mm²</em></h2>
Explanation:
Given the dimension of a paper measured by a ruler as 7.4 cm wide and 8.3 cm long, the area of the paper is expressed using the area for calculating the area of a rectangle as shown;
Area of the piece of paper = Length * Width
Given length = 7.4cm
Length = 74mm (Since 10mm = 1cm)
Width = 8.3cm
Width (in mm) = 83mm
We converted to mm since the ruler used to measure has a division of 1mm.
Substituting the given values into the formula, we will have:
Area of the piece of paper = 74mm * 83mm
Area of the piece of paper = 6,142mm²
<em>Hence, the area of the piece of paper is 6,142mm²</em>
Construct a vector diagram. It will be a right-angled triangle. One vector (the hypotenuse) represents the heading of the boat, one represents the current and one represents the resultant speed of the boat, which I'll call x. Their magnitudes are 20, 3 and x. Let the required angle = theta. We have:
<span>theta = arcsin(3/20) = approx. 8.63° </span>
<span>The boat should head against the current in a direction approx. 8.63° to the line connecting the dock with the point opposite, or approx. 81.37° to the shore line. </span>
<span>x = sqrt(20^2 - 3^2) </span>
<span>= sqrt(400 - 9) </span>
<span>= sqrt 391 </span>
<span>The boat's crossing time = </span>
<span>0.5 km/(sqrt 391 km/hr) </span>
<span>= (0.5/sqrt 391) hr </span>
<span>= approx. 0.025 hr </span>
<span>= approx. 91 seconds</span>
The angular momentum is defined as,
Acording to this text we know for conservation of angular momentum that
Where 
is initial momentum
is the final momentum
How there is a difference between the stick mass and the bug mass, we define that
Mass of the bug= m
Mass of the stick=10m
At the point 0 we have that,
Where l is the lenght of the stick which is also the perpendicular distance of the bug's velocity
vector from the point of reference (O), and ve is the velocity
At the end with the collition we have
Substituting
Applying conservative energy equation we have
Replacing the values and solving
Substituting
l=\frac{13}{0.54(9.8)}
Answer:
Refractive index of unknown liquid = 1.56
Explanation:
Using Snell's law as:
Where,
is the angle of incidence ( 65.0° )
is the angle of refraction ( 53.0° )
is the refractive index of the refraction medium (unknown liquid, n=?)
is the refractive index of the incidence medium (oil, n=1.38)
Hence,
Solving for ,
Refractive index of unknown liquid = 1.56
