Average speed = (distance covered) / (time to cover the distance)
Tissa covered 60 meters in 10 seconds. Her average speed was
(60 m) / (10 sec) = 6 m/s.
That's the slope of the dotted line.
Lilly covered 60 meters in 8 seconds. Her average speed was
(60 m) / (8 sec) = 7.5 m/s .
That's the slope of the solid line.
Lilly covered the same distance in less time, and both girls
arrived at the finish line together. Technically, in science talk,
we would say that Lilly ran "faster", and her average speed
was "greater".
We can detect that by looking at the graph, because Lilly's line
has the characteristic of being "steeper", and we know that the
slope of the line on a distance/time graph is "speed".
As the core collapses, the outer layers of the star are expelled. A planetary nebula is formed by the outer layers. The core remains as a white dwarf and eventually cools to become a black dwarf. ... Like low-mass stars, high-mass stars are born in nebulae and evolve and live in the Main Sequence
hydrogen shell burning - outer layers swell. Red Giant Branch - helium ash core compresses - increased hydrogen shell burning. First Dredge Up - expanding atmosphere cools star - stirs carbon, nitrogen and oxygen upward - star heats up.
Answer:
Part a)
Part b)
Ball thrown downwards =
Ball thrown upwards =
Part c)
Explanation:
Part a)
Since both the balls are projected with same speed in opposite directions
So here the time difference is the time for which the ball projected upward will move up and come back at the same point of projection
Afterwards the motion will be same as the first ball which is projected downwards
so here the time difference is given as
Part b)
Since the displacement in y direction for two balls is same as well as the the initial speed is also same so final speed is also same for both the balls
so it is given as
Part c)
Relative speed of two balls is given as
now the distance between two balls in 0.8 s is given as
Light from other stars take longer to reach the earth because they are farther than our sun.
