The surface area of the sphere is:
A = 4 * pi * r ^ 2
Deriving we have:
A '= 8 * pi * r * r'
We clear the speed:
r '= A' / (8 * pi * r)
Substituting values:
r '= 24 / (8 * pi * 3)
r '= 1 / pi inch / sec
Then, the volume of the sphere is:
V = (4/3) * (pi) * (r ^ 3)
Deriving we have:
V '= (3) * (4/3) * (pi) * (r ^ 2) * (r')
Substituting values:
V '= (3) * (4/3) * (pi) * (3 ^ 2) * (1 / pi)
Rewriting:
V '= (4) * (9)
V '= 36 inch3 / sec
Answer:
the volume of the ice is changing at 36 inch3 / sec at that moment
Answer:
(1 cm)cos3πt
Step-by-step explanation:
Since the piston starts at its maximal height and returns to its maximal height three times evert 2 seconds, it is modelled by a cosine functions, since a cosine function starts at its maximum point. So, its height h = Acos2πft
where A = amplitude of the oscillation and f = frequency of oscillation and t = time of propagation of oscillation.
Now, since the piston rises in such a way that it returns to the maximal height three times every two seconds, its frequency, f = number of oscillations/time taken for oscillation where number of oscillations = 3 and time taken for oscillations = 2 s
So, f = 3/2 s =1.5 /s = 1.5 Hz
Also, since the the piston moves between 3 cm and 5 cm, the distance between its maximum displacement(crest) of 5 cm and minimum displacement(trough) of 3 cm is H = 5 cm - 3 cm = 2 cm. So its amplitude, A = H/2 = 2 cm/2 = 1 cm
h = Acos2πft
= (1 cm)cos2π(1.5Hz)t
= (1 cm)cos3πt
95% is larger because 0.9 is like 90% and 95% is more than 90%
Answer:
x = 7
Step-by-step explanation:
To solve:
Distribute 5 among everything inside the first parentheses. You'll get 5x - 15.
Next distribute -2 among everything in the second parentheses. You'll get
-2x - 2.
<u>All together: 5x - </u><u>15</u><u> </u><u>-</u><u>2x </u><u>-</u><u> </u><u>2</u><u> </u><u>= 4</u>
Now combine like terms:
5x - 2x = 3x and -15 - 2 = - 17
<u>All</u><u> </u><u>together</u><u>: 3x -</u><u> </u><u>17 = 4</u>
Add 17 on both sides to get 21, and then divide both sides by 3. Answer is x = 7.
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Last, don't forget to check your work.
You can plug in 7 for x to get:
5(7 - 3) = 20
5 × 7 = 35
5 × -3 = -15
35 - 15 = 20
-2(7 + 1) = -16
-2 × 7 = -14
-2 × 1 = - 2
-14 -2 = -16
<u>20 - 16 = 4</u>
⬆⬆⬆Therefore this is correct.
Sorry this is a bit lengthy, but hope this helps :)
Answer:
The clock face is divided into sixty equal parts, each minute. The minute hand is located on the 20 minute mark at 6:20, the hour hand located between the 30 minute mark and the 35 minute mark. When the minute hand goes all sixty minutes, the hour hand only moves five, so to figure out the location of the hour hand, we look at how much the hour has progressed, in this case 20 minutes, or one third of the hour. So the minute hand has moved one third of the way through the hour, so has the hour hand moved one third of the way through the five minutes, or, five thirds of a minute, which is one and two thirds minute, one minute forty seconds. That puts the hour hand at thirty minutes plus one minute and forty seconds—at 31min 40sec—which is 11min 40sec farther than the minute hand.
Step-by-step explanation:
