A contour line represents a certain vertical height above the contour line shown. They are means of representing 3D hills and moutains on 2D paper.
2mm.
0,4x 5x10^6 = 2x10^6
1nm = 1x10^-6mm
2x10^6nm = 2mm.
The best thing to do in this case is to redo the experiment and re record the info, it has to be precise and accurate so you also have to check if your procedure is correct. If the results are both accurate and precise then you have to report your findings to the committee of that specific field. <span />
Answer:
Explanation:
Mechanical waves and electromagnetic waves are the types of waves we have. The major difference between this type of waves is that, while mechanical waves requires material medium for its propagation, electromagnetic waves does not require material medium for its propagation.
Example of mechanical waves are waves produced by a ripple tank.
Example of an electromagnetic waves are the electromagnetic spectrum which includes radio waves, infrared waves, visible light, ultraviolet rays etc... This waves are produced naturally without any medium compare to mechanical wave.
The centripetal acceleration of an object is given by the relation,
where Ac = centripetal acceleration = 
R = radius of rotation = 15 m
V = speed of astronaut
Hence, 
solving this we get, V = 38.34 m/s
