Answer:
In terms of distance, average speed is 20 km/h
In terms of displacement, average speed is 0 km/h.
Explanation:
Total distance:
Total time is 3.0 hours
but:
In terms of distance.
substitute:
In terms of displacement:
Answer:
Explanation:
Given
Em wave is in the form of
where 
Wave constant for EM wave k is
Wavelength of wave 
Answer:
c
Explanation:
Friction is caused by how rough and object is, and how much the object weighs, as this causes it to drag more.
The least number of component of a vector quantity is two. These are the x-component and the y-component.
The resultant vector, or vector as we refer to it in this item, can be calculated through the equation,
RV = sqrt ((Vx)² + (Vy)²)
From the equation, it can be noted that if we let Vx equal to zero,
RV = Vy
Similarly, if we let Vy be equal to zero then,
RV = Vx
Thus, it is still possible for the vector to become nonzero even if one of its components is zero.
<span>From the point of view of the astronaut, he travels between planets with a speed of 0.6c. His distance between the planets is less than the other bodies around him and so by applying Lorentz factor, we have 2*</span>√1-0.6² = 1.6 light hours. On the other hand, from the point of view of the other bodies, time for them is slower. For the bodies, they have to wait for about 1/0.6 = 1.67 light hours while for him it is 1/(0.8) = 1.25 light hours. The remaining distance for the astronaut would be 1.67 - 1.25 = 0.42 light hours. And then, light travels in all frames and so the astronaut will see that the flash from the second planet after 0.42 light hours and from the 1.25 light hours is, 1.25 - 0.42 = 0.83 light hours or 49.8 minutes.
