Answer:
(a) V = 0.75 m/s
(b) V = 0.125 m/s
Explanation:
The speed of the flow of the river can be given by following formula:
V = Q/A
V = Q/w d
where,
V = Speed of Flow of River
Q = Volume Flow Rate of River
w = width of river
d = depth of river
A = Area of Cross-Section of River = w d
(a)
Here,
Q = (300,000 L/s)(0.001 m³/1 L) = 300 m³/s
w = 20 m
d = 20 m
Therefore,
V = (300 m³/s)/(20 m)(20 m)
<u>V = 0.75 m/s</u>
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(b)
Here,
Q = (300,000 L/s)(0.001 m³/1 L) = 300 m³/s
w = 60 m
d = 40 m
Therefore,
V = (300 m³/s)/(60 m)(40 m)
<u>V = 0.125 m/s</u>
-- The area under a velocity/time graph, between two points in time, is the difference in displacement during that period of time.
-- The area under a speed/time graph, between two points in time, is the distance covered during that period of time.
Answer: length of B =4.00
Explanation:
for the vectors A and B and the angle between them as x.
Magnitude of the sum of A and B is given as = √(A²+B²+2ABcosx
where
Magnitude of A = 3.00
Magnitude of the sum of A and B is 5.00
5.00=√(A²+B²+2ABcos90°
5.00= √3² +b² +0
5²= 3² +b²
25=9+b²
b²= 25-9
b² = 16
b= √16
b= 4
Answer:
Anna is correct.
Explanation:
Anna is right as a satellite is in free fall because it keeps falling toward Earth, meaning that gravity is the only force acting on it. Tom is incorrect because an object does not have to accelerate at a certain speed to be considered to be in free fall. As long as gravity is the only force acting upon the object, it is considered to be in free fall.
