1) 3 miles/Hour
The speed is defined as the distance covered divided by the time taken:
where
d = 1.5 mi is the distance
t = 0.5 h is the time taken
Substituting,
2) 1.34 m/s south
Velocity, instead, is a vector, so it has both a magnitude and a direction. We have:
is the displacement in meters
is the time taken in seconds
Substituting,
And the direction of the velocity is the same as the displacement, so it is south.
I'd say b, precise, here.
If there's an error somewhere in the experiment or project, then it is consistently .... wrong. So, just 'cos you measure something precisely, it doesn't mean that you've measured it accurately. Maybe an example would be a measurement of length. If you used a metal ruler at zero degrees C, you can measure to say half a millimetre. A series of measurements of the same object would give very similar readings. But, if you used same metal ruler at, say 100 celsius (implausible) then you'd probably get a different set of readings. 'cos of the expansion of the metal ruler.
Because the refractive indexes of the immersion oil and the glass microscope slide are the same; the oil prevents the refraction of the incoming light rays.
An invisible space is present between the slide and the lens that contains air.
When the light rays fall on the slide and lens they might get refracted due to air present between them.
If the rays get refracted then the diameter of the objective lens will expand further.
So in order to prevent the refraction of light, it is very important to lubricate the surface of the lens because without oil the light rays refract from their original path.
If you need to learn more about the refractive index click here
brainly.com/question/5170843
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Answer:
B
Explanation:
<em>A. His speed is 0 m/s
</em>
<em>B. His velocity is 12 m/s
</em>
<em>C. His velocity is 0 m/s
</em>
<em>D. His acceleration is 12 m/s</em>
Total distance traveled by John = 120 + 120 = 240 meters
Total time taken by John to cover the distance = 10 + 10 = 20 s
<em>Average speed of John = total distance traveled/total time taken</em>
= 240/20 = 12 m/s
Hence, the average speed/velocity of John throughout the journey is 12 m/s.
The correct option is B.
