20/45=0.4*100= 44.4 so the answer is..................................................
Answer: 44.4%
The third choice is correct
Answer:
Different star constellations are visible from Earth at different seasons of the year.
Explanation:
The reason the fact that we can see different constellations in the sky during different seasons on earth is the most compelling reason we travel around the sun is because if the sun travelled around the earth, certain constellations would only be visible in certain places. You’d have to travel to see certain ones.
However, you don’t have to do that because we travel around the sun, therefore travelling around other stars too.
Answer:
Part 1) Time of travel equals 61 seconds
Part 2) Maximum speed equals 39.66 m/s.
Explanation:
The final speed of the train when it completes half of it's journey is given by third equation of kinematics as
where
'v' is the final speed
'u' is initial speed
'a' is acceleration of the body
's' is the distance covered
Applying the given values we get
Now the time taken to attain the above velocity can be calculated by the first equation of kinematics as
Since the deceleration is same as acceleration hence the time to stop in the same distance shall be equal to the time taken to accelerate the first half of distance
Thus total time of journey equals
Part b)
the maximum speed is reached at the point when the train ends it's acceleration thus the maximum speed reached by the train equals