In science, the metric units are most often the units used for experiments. These units are not often used in America otherwise.
Explanation:
Given that, the height of the tide measured at a seaside community varies according to the number of hours t after midnight. The height is given by the equation as :

When the tide first be at 6 ft, put h = 6 ft in above equation as :

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On solving the above equation to find the value of t. It is equal to :
t = 3.551 seconds
or
t = 8.449 seconds
So, the tide of 6 ft is at 3.551 seconds and 8.449 seconds. Hence, this is the required solution.
Answer:
Impedance = 93.75 ohms
Current = 1.81 A
Explanation:
Resistance = R = 80 ohms
Inductance = L = 0.2 H
Inductive reactance = XL =
= ωL = (2πf) L
= 2 (3.14) (60)(0.2) = 75.398 Ohms
Capacitive reactance = 1 / ωC = 1/(2πf)C = 1 / [(2π)(60)(0.1 × 10⁻3)]
= 26.526 Ohms
Impedance = Z =
=
= 93.747 ohms
Voltage =
× 120 = 169.7056 V
Current = I = V ÷ R = (169.7056) ÷ 93,747 = 1.81 A
Answer: The Northern Hemisphere experiences the start of <u>summer</u>
Explanation:
Due to this tilt in Earth's axis of rotation, some regions receive different amounts of sunlight according to the seasons of the year. These variations are more evident near the poles and softer or imperceptible near the equator. This explains the fact that while in the northern hemisphere it is summer and there are high temperatures (because the Sunlight incides more perpendicularly in this area during this season), in the southern hemisphere it is winter and very low temperatures are recorded, and vice versa.
In this sense, according to the image the Earth is at the point of its orbit in which, due to the inclination of its axis, the North Pole is closer to the Sun.
In other words, the northern hemisphere is tilted toward the Sun, and this astronomical phenomenon brings the summer season for the Northern Hemisphere.
Answer:
Explanation:
Work is defined as the scalar product of force and distance
W=F•d
Given that
F = 8.5i + -8.5j. +×-=-
F=8.5i-8.5j
d = 2.5i + cj
If the work in the practice is zero, then W=0
therefore,
W=F•ds
0=F•ds
0=(8.5i -8.5j)•(2.5i + cj)
Note that
i.i=j.j=k.k=1
i.j=j.i=k.i=i.k=j.k=k.j=0
So applying this
0=(8.5i -8.5j)•(2.5i + cj)
0= (8.5×2.5i.i + 8.5×ci.j -8.5×2.5j.i-8.5×cj.j)
0=21.25-8.5c
Therefore,
8.5c=21.25
c=21.25/8.5
c=2.5