Answer:
Step-by-step explanation:
We have to write 243 as a power of some number.
So, if we factorize 243 we get,
243 = 3 × 3 × 3 × 3 × 3
Therefore, we can write 243 as a power of 3.
No other number can be written in powers of 243 because it do not contain any other factor than 3.
Hence, 243 can be written as :
Answer:
The tip of the man shadow moves at the rate of
Step-by-step explanation:
Let's draw a figure that describes the given situation.
Let "x" be the distance between the man and the pole and "y" be distance between the pole and man's shadows tip point.
Here it forms two similar triangles.
Let's find the distance "y" using proportion.
From the figure, we can form a proportion.
Cross multiplying, we get
15(y -x) = 6y
15y - 15x = 6y
15y - 6y = 15x
9y = 15x
y =
We need to find rate of change of the shadow. So we need to differentiate y with respect to the time (t).
----(1)
We are given . Plug in the equation (1), we get
Here the distance between the man and the pole 45 ft does not need because we asked to find the how fast the shadow of the man moves.
Answer:
150.51 dB
Step-by-step explanation:
Data provided in the question:
decibel level of sound at 161 km distance = 180 dB
d₁ = 161 km
d₂ = 4800 km
I₁ = 180 db
The formula for intensity of sound is given as:
I =
and the relation between intensity and distance is given as:
I ∝
or
Id² = constant
thus,
I₁d₁² = I₂d₂²
or
therefore,
I =
or
I =
or
I = 20 × (-1.474)
or
I = -29.49
Therefore,
the decibel level on Rodriguez Island, 4,800 km away
= 180 - 29.49
= 150.51 dB