1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
charle [14.2K]
3 years ago
10

The height of the tide measured at a seaside community varies according to the number of hours t after midnight. If the height h

, in feet, is currently given by the equation h=-1/2 t^2+6t-9, when will the tide first be at 6 ft?
Physics
1 answer:
antoniya [11.8K]3 years ago
6 0

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 :

h=-\dfrac{1}{2}t^2+6t-9

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

-\dfrac{1}{2}t^2+6t-9=6

-t^2+12t-18=0

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.

You might be interested in
Plz, help the rubber ball be dropped from the top of a ladder. It bounces on the same spot on the ground several times to a less
Vladimir [108]

Answer:

What do you mean?

Explanation:

6 0
2 years ago
The electric field strength between the plates of a simple air capacitor is equal to the voltage across the plates divided by th
Dmitry [639]

Answer:

d = V/E

Explanation:

From the definition, we can say that the electric field strength between the plates of a parallel plate capacitor is

E = v/d

where

E = electric field strength

V = potential difference

d = distance between the plates

On rearranging the equation and making d subject of the formula, we have

d = V/E

From the question, we're given that

V = 112 V

E = 1.12 kV/cm converting to V/m, we have 110000 V/cm

d = 112 / 110000

d = 0.00102 m

d = 1.02*10^-3 m

5 0
3 years ago
A friend tells you that a lunar eclipse will take place the following week, and invites you to join him to observe the eclipse t
WARRIOR [948]

Answer:

y = 80.2 mille

Explanation:

The minimum size of an object that can be seen is determined by the diffraction phenomenon, if we use the Rayleigh criterion that establishes that two objects can be distinguished without the maximum diffraction of a body coincides with the minimum of the other body, therefore so much for the pupil of the eye that it is a circular opening

          θ = 1.22 λ/ d

in a normal eye the diameter of the pupils of d = 2 mm = 0.002 m, suppose the wavelength of maximum sensitivity of the eye λ = 550 nm = 550 10⁻⁹ m

         θ = 1.22 550 10⁻⁹ / 0.002

         θ = 3.355 10⁻⁴ rad

Let's use trigonometry to find the distance supported by this angle, the distance from the moon to the Earth is L = 238900 mille = 2.38900 10⁵ mi

       tan θ = y / L

       y = L tan θ

       y = 2,389 10⁵ tan 3,355 10⁻⁴

       y = 8.02 10¹ mi

       y = 80.2 mille

This is the smallest size of an object seen directly by the eye

5 0
3 years ago
A capacitor consists of two parallel plates, each with an area of 17.0 cm2 , separated by a distance of 0.150 cm . The material
Llana [10]

Answer:

a) C = 40.138\,pF, b) q = 16.056\,nC, c) U = 3.212\,\mu J

Explanation:

a) The capacitance of two parallel plates capacitor with dielectric is given by the following expression:

C = K\cdot \epsilon_{o}\cdot \frac{A}{d}

Where:

K - Dielectric constant.

\epsilon_{o} - Vaccum permitivity.

A - Plate area.

d - Distance between plates.

Hence, the capacitance of the system is:

C = (4.00)\cdot (8.854\times 10^{-12}\,\frac{F}{m} )\cdot \left(\frac{17\times 10^{-4}\,m^{2}}{0.150\times 10^{-2}\,m}\right)

C = 4.014\cdot 10^{-11}\,F

C = 40.138\,pF

b) The charge can be found by using the definition of capacitance:

q = C\cdot V_{batt}

q = (4.014\times 10^{-11}\,F)\cdot (400\,V)

q = 1.606\times 10^{-8}\,C

q = 16.056\,nC

c) The energy stored in the charged capacitor is:

U=\frac{1}{2}\cdot Q\cdot V_{batt}

U=\frac{1}{2}\cdot (1.606\times 10^{-8}\,C)\cdot (400\,V)

U = 3.212\times 10^{-6}\,J

U = 3.212\,\mu J

3 0
3 years ago
Read 2 more answers
What is the time it takes an object that moves at 25 m/min to travel 505 meters?
Mrac [35]

Answer:

25 meters = 1 minute

505 meters = ? minutes

Therefore, 505/25

Therefore, 101/5

Therefore, 2.2 minutes

It moves 505 meters in 2.2min

7 0
3 years ago
Other questions:
  • Which of these is a type of telescope?
    5·2 answers
  • Does melting change substances into other substances?
    7·2 answers
  • The Cosmoclock 21 Ferris wheel in Yokohama City, Japan, has a diameter of 100 m. Its name comes from its 60 arms, each of which
    9·1 answer
  • If an object accelerates at 10 m/s2 for 4 seconds, how much will its velocity change by?
    13·1 answer
  • How facts differ from theroies?
    5·2 answers
  • Two students, standing on skateboards, are initially at rest, when they give each other a shove! After the shove, one student (7
    14·1 answer
  • This planet orbit around the sun cuts across the path of another planet.
    10·1 answer
  • The picture to the right shows which wave behavior?
    15·2 answers
  • All objects in our solar system orbit the Sun. How is the movement of planets like
    12·1 answer
  • Can and object have a negative position and a positive velocity? Or vice versa, a positive position and a negative velocity? Exp
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!