Answer:
Average speed = distance/time
From 1 to 9 seconds:
Distance covered = 1 - 0.2 = 0.8 km
Time = 9 - 1 = 8 sec
Average speed = 0.8 km / 8 sec
Average speed = 0.1 km/s .
The average speed for the whole test is 1.6 km / 20 sec = 0.08 km/sec. A graph of speed vs time would average out as a horizontal line at 0.08 km/sec from 1 sec to 21 sec. The area under it would be (0.08 km/s) x (20 sec) = 1.6 km.
Surprise surprise ! The area under a speed/time graph is the distance covered during that time !
In closing, I want to express my gratitude for the gracious bounty of 3 points with which I have been showered. Moreover, the green breadcrust and tepid cloudy water have also been refreshing.
Explanation:
Part A:
For this part we’re assuming all the kinetic energy of the moving bumper car is converted into elastic potential energy in the spring since the car is brought to rest. Therefore you can find the total kinetic energy to get your answer:
KE = ½ mv^2
KE = ½ (200)(8)^2
KE = 6400 J
Part B:
Now you can use Hooke’s law to find the force:
F = kx
F = (5000)(0.2)
F = 1000 N
La capoeira se desarrolló en Brasil, derivada de las tradiciones traídas a través del Océano Atlántico por africanos esclavizados y alimentadas por el ardiente deseo de libertad. Pronto se practicó ampliamente en las plantaciones como un medio para romper los lazos de la esclavitud, tanto física como mentalmente.
The question is somewhat ambiguous.
-- It's hard to tell whether it's asking about '3 cubic meters'
or (3m)³ which is actually 27 cubic meters.
-- It's hard to tell whether it's asking about '100 cubic feet'
or (100 ft)³ which is actually 1 million cubic feet.
I'm going to make an assumption, and then proceed to
answer the question that I have invented.
I'm going to assume that the question is referring to
'three cubic meters' and 'one hundred cubic feet' .
OK. We'll obviously need to convert some units here.
I've decided to convert the meters into feet.
For 1 meter, I always use 3.28084 feet.
Then (1 meter)³ = 1 cubic meter = (3.28084 ft)³ = 35.31 cubic feet.
So 3 cubic meters = (3 x 35.31 cubic feet) = 105.9 cubic feet.
That's more volume than 100 cubic feet.
