Average speed of the runner is the rate at which the runner covers the total distance. Average speed of the runner in the race is given by,
Average speed = 
Where
Total distance = Distance covered by the runner from initial to final position
Total time = time taken by the runner to cover entire distance
Instantaneous speed is the speed of the runner at the particular moment in the given time. Instantaneous speed is given by,
Instantaneous speed = 
x = position of the runner at time t
t = time taken to cover distance x
Hence, Average speed and instantaneous speed are different for a runner running in the race.
Answer:
T² ∝ R³
Explanation:
Given data,
The period of revolution of the planet around the sun, T
The mean distance of the planet from the sun, R
According to the III law of Kepler, " Law of Periods' states that the square of the orbital period to go around the sun once is directly proportional to the cube of the mean distance between the sun and the planet.
T² ∝ R³
From the above equation it is clear that T² varies directly as the R³.
264 km
72 x 3 hr = 216 km
72/60 (min in an hr) = 1.2(km per min) x 40 = 48 km
216 + 48 = 264
<h2>Movement of Continents</h2>
Explanation:
- Alfred Wegener was a German astronomer who proposed the "continental drift" hypothesis in 1910.
- Alfred Wegener was not able to explain the movements of the continent in how and in which way they are moved.
- He failed in an attempt to explain with the use of tides made the theory undefinable fully.
- Also, the major problem with Wegener's theory of Continental Drift was that there was no proper explanation of a mechanism.
