<u>Answer:</u>
<em>The average speed of the car is 66.9 km/h</em>
<u>Explanation:</u>
Here distance covered with the speed <em>57 km/h=7 km </em>
distance covered with the speed of <em>81 km/h=7 km</em>
<em>Average speed is equal to the ratio of total distance to the total time.
</em>
<em>total distance= 7 + 7= 14 km </em>
<em>
</em>
<em>time taken to cover the first 7 km= 7/57 h </em>
<em>time taken to cover the second part of the journey = 7/81 h
</em>
<em>average speed =
</em>
<u><em>Shortcut:
</em></u>
<em>When equal distances are covered with different speeds average speed=2 ab/(a+b) where a and b are the variable speeds in the phases.
</em>
Let's start by differentiating the terms distance and displacement. They both refer to the length of paths. Distance only accounts for the total length regardless of the path taken. Displacement measures the linear path from the starting point to the end point. So, it does not necessarily follow the actual path. However, for this problem, assuming that the path is just in one direction, displacement and distance would just be equal. The equation would be:
Distance = Displacement = v₀t + 0.5at² = 0(10 s) + 0.5(+1.2 m/s²)(10 s)²
Distance = Displacement = 60 meters
Answer:
I think it is 5.6. This is my answer
<h2>
Answer: True </h2><h2>
</h2>
Each atom emits or absors electromagnetic radiation, but only in some frequencies that are characteristic of its chemical element.
Now, if we supply energy in the form of heat (thermal energy) to a certain element in its gas phase, this will be stimulated and its atoms will emit radiation in certain frequencies of the visible spectrum, which constitute its <u>emission spectrum</u>.
If the same element, also in gaseous state, receives electromagnetic radiation, it absorbs in certain frequencies of the visible spectrum, <u>precisely the same ones in which it emits when it is stimulated by heat</u>. This will be its <u>absorption spectrum.</u>
<h2>
This means that every element absorbs radiation in the same wavelengths in which it emits it. </h2>
The orbital radius is: 
Explanation:
The problem is asking to find the radius of the orbit of a satellite around a planet, given the orbital speed of the satellite.
For a satellite in orbit around a planet, the gravitational force provides the required centripetal force to keep it in circular motion, therefore we can write:

where
G is the gravitational constant
M is the mass of the planet
m is the mass of the satellite
r is the radius of the orbit
v is the speed of the satellite
Re-arranging the equation, we find:

Learn more about circular motion:
brainly.com/question/2562955
brainly.com/question/6372960
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