A pendulum clock is taken to the moon (g = 1.6 N/kg). How long must the pendulum be in order for the clock to
continue keeping accurate time (1 second cycle)?
3.2 m
7.9 m
0 0.25 m
0.041 m

Answers

Answer 1

Answer:

0.041 m

Explanation:

T = 2π√(L/g)

1 s = 2π√(L / (1.6 N/kg))

L = 0.041 m

Answer 2

Answer:

0.041

Explanation:

got right on test!


Related Questions

A scientist wants to measure the relationship between humidity in the
summer and the number of home runs in baseball. Which of the following is a
testable question about this topic?
A. Are home runs more fun to watch than normal hits?
B. Are home runs more exciting during the summer?
C. Are there more home runs during the more humid months of the
summer?
D. Should fans like the players who hit the most home runs?

Answers

Answer:

i think option c is correct answer.

"Fun", "exciting", and "like" cannot be scientifically tested. They're perceived differently by different people, and they may even be perceived differently by the same person on different days.

Option-C is the only testable question on this list.

Compare and contrast electromagnetic force, electromagnetic waves, and an electromagnetic field

Answers

Electromagnetic field" just refers to the field created by static (electric field) or moving (magnetic field) charges. An electromagnetic wave is a certain configuration of the electromagnetic field. The key is that an electromagnetic wave is not constant--it oscillates with time.

Electromagnetic fields are a combination of invisible electric and magnetic fields of force.

Electromagnetic waves  is a way or path to represent electromagnetic field

When conductor comes in an Electromagnetic field the electromagnetic waves exerts a force on it called  electromagnetic force

What are electromagnetic waves?

Electromagnetic waves or EM waves are waves that are created as a result of vibrations between an electric field and a magnetic field.

Electromagnetic fields are a combination of invisible electric and magnetic fields of force.

Electromagnetic waves or EM waves are waves that are created as a result of vibrations between an electric field and a magnetic field. It is a way or path to represent electromagnetic field

When a conductor is placed in a magnetic field and current flows in the conductor, the magnetic field and the current interact each other to produce force. The force is called "Electromagnetic force". When conductor comes in an Electromagnetic field the  electromagnetic waves exerts a force on it called  electromagnetic force

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In general, the the string or air column of a musical instrument is, the more harmonics are generated.

Answers

Answer:

In general, the LONGER the string or air column of a musical instrument is, the more harmonics are generated.

ASSIGNMENTS
COURSES
Assignment
Attempt 1 of 3
SECTION 101
QUESTION 9 OF 35
A box is suspended from a series of cables as shown below. The angle of the cable attached to the ceiling is 30°
relative to the horizontal. The cable to the left has a tension force of 40 N. What is the approximate weight of the box?
30°
40N
23N

Answers

Answer:

23 N

Explanation:

By using the diagram above

[tex] \tan(30) = \frac{x}{40} [/tex]

By cross multiplying

[tex]x = \tan(30) \times 40[/tex]

[tex]x = 0.577 \times 40[/tex]

[tex]x = 0.577 \times 40[/tex]

[tex] x = 23.08[/tex]

[tex]approximately \: 23 [/tex]

3. How do we measure the average kinetic motion of molecules in a solution?

Answers

The translational kinetic energy of of an ideal gas can be found by multiplying the formula for the average translational kinetic energy by the number of molecules in the sample.

A stone was projected at an angle of 40o and initial velocity of 20m/s. (a.)Determine the time of flight  (b)Maximum height.

Answers

Answer:

A.) 1.3 seconds

B.) 0.42 m

Explanation:

A.) You are given the angle of projection to be 40 degrees and initial velocity of 20m/s. 

At vertical component

U = Usin 40 that is,

U = 20sin40

Using the first equation of motion under gravity

V = U - gt

Let V = 0

0 = UsinØ - gt

gt = UsinØ

t = UsinØ/g

Where U = 20 m/s

Ø = 40 degree

g = 9.8 m/s^2

Substitutes all the parameters into the formula

t = 20sin40/9.8

t = 1.3 seconds

Total time of flight T = 2t

T = 2 × 1.3 = 2.6 s

B.) To calculate the maximum height,

You will use the formula

V^2 = U^2 - 2gH

At maximum height, V = 0

2gH = Usin^2Ø

H = Usin^2Ø/ 2g

Substitutes all the parameters into the formula

H = 20 sin^2(40) ÷ 2(9.8)

H = 8.2635/19.6

H = 0.42 m

QUESTION 35
How is it possible for a stuntman to drop from a two-story building onto a mattress and not be injured?
A. The mattress increases the impact.
OB. The mattress decreases the time of the impact
C. The mattress decreases the man's force.
D. The mattress increases the time of the impact

Answers

Answer:

C. The mattress decreases the man's force.

Explanation:

Has to be c

Answer:

C. becuase this would make the man survive.

14. Which of the following ray diagrams is correct for the mirror shown?

Answers

Answer:

C is the correct answer

Answer:

B

Explanation:

Which of the following is the best thermal insulator
A. Air
B. Iron
C. Water
D. Aluminum

Answers

Answer: a. air

Explanation:

Generally, the lower the density of the material, the better insulator the material is: this is because in materials with very low density, particles are very spread apart, so they cannot collide with each other, and so the vibrations of the particles (which determine how hot a substance is) cannot be transmitted very efficiently.

In the options listed in this problem, air is the material with lowest density, therefore it is the best thermal insulator among them.

Answer:

A. Air

Explanation:

It is correct in Ареx.

Which statement best describes scientific theories?


A. Scientific theories attempt to explain an entire group of related phenomena.

B. Scientific theories are based on facts that describe natural events.

C. Scientific theories describe natural events but do not explain them.

D. Scientific theories are facts based on observations of events in the natural world.

Answers

Answer:

the answer is A

Explanation:

Scientific theories attempt to explain an entire group of related phenomena.

Scientific theories attempt to explain an entire group of related phenomena. The correct option is A.

What is scientific theory?

A scientific theory is a well-thought-out explanation for natural-world observations that has been built using the scientific method and incorporates many facts and hypotheses.

A scientific law predicts the outcome of a set of initial conditions. It could predict your unborn child's hair color or the distance a baseball travels when launched at a specific angle.

A theory, on the other hand, attempts to provide the most logical explanation for why things happen the way they do.

Scientific theories attempt to explain a broad range of phenomena. A theory not only explains known facts; it also allows scientists to predict what they will see if the theory is correct.

Thus, the correct option is A.

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A camera lens focuses on an object 75.0 cm from the lens. The image forms 3.50 cm behind the lens. What is the magnification of the image?

Answers

Answer:

- 0.0466666667

Explanation:

We are told in the question above that:

A camera lens focuses on an object 75.0 cm from the lens. The image forms 3.50 cm behind the lens.

The formula for Magnification of an image = - image distance / object distance

Image distance = 3.50 cm

Object distance = 75 cm

Magnification = - 3.5/75

= -0.0466666667

= Approximately = -0.0467

Therefore, the magnification of the image is -0.0467

Answer:

0.557

Explanation:

That's the answer to a similar problem that asks us to solve for how tall the image is.

if it's 12.4 cm tall

correct for Acellus

This one:

A camera lens focuses on an image 78.0 cm from the lens

The image is 3.5 cm behind the lens

If it's 12.4 cm tall, how tall is the image

hope it helps

A hollow, uniformly charged sphere has an inner radius of r1 = 0.105 m and an outer radius of r2 = 0.31 m. The sphere has a net charge of Q = 1.9 μC. What is the magnitude of the electric field, in newtons per coulomb, at a distance of r = 0.17 m from the center of the sphere?

Answers

Answer:

E = 77532.42N/C

Explanation:

In order to find the magnitude of the electric field for a point that is in between the inner radius and outer radius, you take into account the Gauss' law for the electric flux trough a spherical surface with radius r:

[tex]\int E\cdot dS=\frac{Q}{\epsilon_o}[/tex]       (1)

Q: net charge of the hollow sphere = 1.9*10-6C

ε0: dielectric permittivity of vacuum = 8.85*10^-12 C^2/Nm^2

Furthermore, you have that the net charge contained in a sphere of radius r is:

[tex]Q=\rho V=\rho \frac{4\pi (r^3-r_1^3)}{3}[/tex]      (2)

with the charge density is:

[tex]\rho=\frac{Q}{\frac{4}{3}\pi(r_2^3-r_1^3)}[/tex]          (3)

r2: outer radius = 0.31m

r1: inner radius = 0.105m

The electric field trough the Gaussian surface is parallel to the normal to the surface, the, you have in the integral of the equation (1):

[tex]\int E\cdot dS=E(4\pi r^2)[/tex]      (4)

where you have used the expression for a surface of a sphere.

Next, you replace the expressions of equations (2), (3) and (4) in the equation (1) and solve for E:

[tex]E(4\pi r^2)=\frac{1}{\epsilon_o}\frac{Q}{\frac{4}{3}\pi(r_2^3-r_1^3)}(\frac{4\pi (r^3-r_1^3)}{3})\\\\E=\frac{1}{\epsilon_o}\frac{Q(r^3-r_1^3)}{4\pi r^2(r_2^3-r_1^3)}[/tex]

you replace the values of all parameters, and with r = 0.17m

[tex]E=\frac{(1.6*10^{-6}C)((0.17m)^3-(0.105m)^3)}{4\pi(8.85*10^{-12}C^2/Nm^2)(0.17m)^2((0.31m)^3-(0.105m)^3)}\\\\E=77532.42\frac{N}{C}[/tex]

The magnitude of the electric field at a distance r=0.17m to the center of the hollow sphere is 77532.42N/C

What happens to the object if the line crosses the x-axis from the positive portion of a velocity versus time diagram?

Answers

Answer:

A velocity time graph shows the change of velocity of an object with respect ot time. If the slope of the graph is increasing in the postive region, it means that the velocity is changing, if the slope is decreasing, it means the the velocity is decreasing, but the object is moving in the same direction (positve direction).

If this slope intersects the graph at x-axis, it means that the body has 0 velocity and has become still. After that, if the line enters in the negative region, it means that its velocity is started to increases again, but the body is movinging in the opposite direction (negative direction)

At which point does the planet have the least gravitational force acting on it?

Answers

Answer:

At which point does the planet have the least gravitational force acting on it?

Explanation:

In an elliptical orbit, when a planet is at its furthest point from the Sun, it is under the least amount of gravity, meaning that the force of gravity is strongest when it is closest.

Answer:

Point A

Explanation:

Recall that gravitational force is inversely proportional to the square of the distance between the 2 objects.

This means that the farther away the objects are from each other, the lesser their gravitational interaction will be.

In this case we can see that Point A is furthest away from the star, hence this will be the location with the least gravitational force from the star.

Which optical devices spread light apart?
A. A and B
B. A and D
C. B and D
D. B and C

Answers

[tex]\mathfrak{\huge{\pink{\underline{\underline{AnSwEr:-}}}}}[/tex]

Actually Welcome to the Concept of the Optical Devices.

Now basically here the devices that can spread light over apart are the CONCAVE LENS and Convex mirror.

so the Answer is

C. B and D

The optical devices that spread light apart is B and D.

What are optical devices?

Optical devices are implements or instruments that process,analyses light waves and interprete it in order to enhance an image for visibility and determine the features of such image.

Therefore, The optical devices that spread light apart is B and D.

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Diagram 1 shows a beam balance. A beaker with a wire loop balances the standard masses. The beaker is then removed and hung from a spring. The spring extends by 5.0 cm, as in diagram 2. The experiment is repeated with the same apparatus on the Moon, where the acceleration of free fall is less than on Earth. Which statement describes what happens on the Moon? A. The beam balance is balanced and the spring extends by 5.0 cm. B. The beam balance is balanced and the spring extends by less than 5.0 cm. C. The right-hand balance pan is higher and the spring extends by 5.0 cm. D. The right-hand balance pan is higher and the spring extends by less than 5.0 cm.

Answers

Answer:

the answer would be A

Explanation:

The lack of ________ between the train and the tracks allow the train to reach unbelievable speed.

Answers

Answer:

Friction

Explanation:

Friction is the force that is created when two objects rub against each other. All objects are rough, even though it might not appear that way, on the microscopic scale. These little grooves and ridges get stuck against each other when two objects are moved against each other, and they slow down motion. If there is no friction between a train and its tracks, then it can continue to accelerate without slowing down. Hope this helps!

The answer is definitely friction

A 15.0 cm object is 12.0 cm from a convex mirror that has a focal length of -6.0 cm. What is the height of the image produced by the mirror? A. –5.0 cm B. 7.5 cm C. -7.5 cm D. 5.0 cm

Answers

Answer: D. 5cm

Explanation:

Given the following :

Focal length (f) = - 6.0 cm

Height of object = 15.0cm

Distance of object from mirror (u) = 12.0cm

Height of image produced by the mirror =?

Firstly, we calculate the distance of the image from the mirror.

Using the mirror formula

1/f = 1/u + 1/v

1/v = 1/f - 1/u

1/v = 1/-6 - 1/12

1/v = - 1/6 - 1/12

1/v = (- 2 - 1) / 12

1/v = - 3 / 12

v = 12 / - 3

v = - 4

Using the relation :

(Image height / object height) = (- image distance / object distance)

Image height / 15 = - (-4) / 12

Image height / 15 = 4 / 12

Image height = (15 × 4) / 12

Image height = 60 / 12

Image height = 5cm

Answer:

D. 5 cm

Explanation:got it right

A graph titled Position versus Time shows time in seconds on the x axis, numbered 0 to 5, position in meters on the y axis, numbered 0 to 4. The graph has a horizontal line starting at (0, 3) to (5, 3). Given the information in the velocity vs. time graph, what is the displacement of the object after 1 second? m After 3 seconds? m After 5 seconds? m

Answers

Answer:

After 1 second: 3

After 3 seconds: 9

After 5 seconds: 15

Explanation:

You just multiply the time and velocity.

1 x 3 = 3, 3 x 3 = 9, etc.

Answer:

C.) The bicycle is not in motion.

Explanation:

which of the following does not negatively affect the health of a watershed? A. Surface runoff from roads, sidewalks, and roofs. B. Sewer overflow from combined sewer systems. C. Wilderness areas. D. Chemicals used on farmland.

Answers

Answer:

A. Surface runoff from roads, sidewalks, and roofs

C. Wilderness areas.  will mostly likely not affect the health of watershed

Explanation:

Options A and C are not really harmful to the health of watershed, but chemicals used on farmlands and overflow from combined sewer systems can contaminate watershed adversely, which can be a major cause of the cholera outbreak (a water borne disease)

How is a voltmeter used in a circuit?
A. It is connected in series and measures current.
B. It is connected in parallel and measures potential difference.
C. It is connected in parallel and measures current.
D. It is connected in series and measures potential difference.

Answers

Answer:

Explanation:

A voltmeter is usually connected in parallel with a part of a complete circuit.  The meter itself is connected in series to a very high resistance so that the amount of current drained is very tiny.

So you see, you could answer this in two ways, but since you are asking a question at a very beginning level, I think the answer should be

B

because voltmeters are made to measure potential difference and they are placed in parallel to the part measured. How it works is interesting but is not really part of the question.

Answer:

B. It is connected in parallel and measures potential difference.

Explanation:

A voltmeter is connected in parallel.

A voltmeter is used for measuring the electrical potential difference between two points in an electric circuit.

The binding energies of all nuclei are negative. true or false

Answers

Answer:

False.

Explanation:

Nuclei decay from a more stable form to a less stable form.

Answer:

False

Explanation:

A fire truck drives 3 miles to the east, then 1.2 miles to the west. What is the
displacement of the fire truck?
A. 4.2 miles east
B. 4.2 miles west
C. 4.2 miles
D. 1.8 miles east

Answers

Answer:

the answer is D. you have to go 3 miles to the east and then subtract the distance that the fire truck traveled to the the west.

Answer: D. 1.8 miles east

Explanation:

(Each "→" or "←" = .2 miles)

3 miles east:                →→→→→ →→→→→ →→→→→

minus 1.2 miles west:                       ← ←←←←←

3 - 1.2 = 1.8 miles east: →→→→→ →→→→

Which factor causes atmospheric pressure? A. Altitude above sea level. B. Weight of the atmosphere above the surface. C. Air currents in the atmosphere over the ocean. D. Sizes and shapes of clouds.

Answers

Answer:

B. Weight of the atmosphere above the surface.

Explanation:

The pressure that the atmosphere of the earth exerts is termed to be the atmospheric pressure. This pressure is applied on the surface of the air because of the gravitational pull. With the increase in altitude, the atmospheric pressure decreases. The atmospheric weight pushes itself downwards because of the gravity, this creates the pressure. The factor that causes atmospheric pressure is the 'Weight of the atmosphere above the surface.'

What is the wave speed of a wave that has a frequency of 50 Hz and a wavelength of 0.10 m? What is the frequency of a wave that has a wave speed of 20 m/s and a wavelength of 0.50 m?

Answers

Answer:

a) What is the wave speed of a wave that has a frequency of 50 Hz and a wavelength of 0.10 m?

5m/s

b) What is the frequency of a wave that has a wave speed of 20 m/s and a wavelength of 0.50 m?

40Hz

Explanation:

a) What is the wave speed of a wave that has a frequency of 50 Hz and a wavelength of 0.10 m?

Wave speed(v) = Frequency(f) × Wavelength (λ)

= 50Hz × 0.10m

=5m/s

b) What is the frequency of a wave that has a wave speed of 20 m/s and a wavelength of 0.50 m?

The formula for Frequency when given wave speed and wave length = Wave speed/ wave length

f = v/λ

Frequency = 20m/s ÷ 0.50m

Frequency = 40Hz

Answer:

40 Hz

Explanation:

Question is in the uploaded photo

Answers

Answer:

1) Mass of the string = 0.0267kg

Explanation:

1) In the above question, we are given:

Length of guitar string = 60cm

Wave speed = 30.0m/s

Tension = 50N

9.81 N = 1 kg

50N = 50/9.81

= 5.10kg

We have the formula

v = √(F/μ)

Where F = the tension in the string in newtons,

v = the wave speed in m/s

μ = the mass per unit length of the string in kg/m

The formula for μ is derived as

v = √(F/μ)

Square both sides

v² = [√(F/μ)]²

v² = F/μ

μ = F/v²

From the question,

μ = 40/ 30.0²

μ = 0.044kg/m

To calculate the mass of the string we use the formula

μ = Mt / Lt = total mass/total length.

Total length = 60cm

In meters = 0.60m

0.044kg/m = Mt/ 0.60m

Mt = 0.0266666667kg

Mass of the string = Approximately 0.0267kg

2)

Suppose the initial position of an object is zero, the starting velocity is 3 m/s and the final velocity was 10 m/s. The object moves with constant acceleration. Which part of a velocity vs. time graph can be used to calculate the displacement of the object?

the area of the rectangle under the line
the area of the rectangle above the line
the area of the rectangle plus the area of the triangle under the line
the area of the rectangle plus the area of the triangle above the line

Answers

Answer:

The area of the rectangle plus the area of the triangle under the line

Explanation:

In this case, the object moves with constant acceleration. Initial speed of the object is 0.

Equation of kinematics :

v = u +at

v = at

v is directly proportional to time. If means that the graph is straight line passing through origin. We know that area under v-t graph gives displacement. So, the correct option is (c).

Answer:

c) the area of the rectangle plus the area of the triangle under the line

Explanation:

edge2021

this is a non graded disscussion i want to fill out it is just a worksheet to help me get better 30 points

Answers

Answer:

1.) 30m/s

2) 5m/s

3) 40Hz

4) 400Hz

5) 300Hz

6) 0.77m

7) 0.386m

8) 0.625m

9) 100m/s

10) 50m/s

Explanation:

The speed of a wave (V) equals :

V = fλ ; where f = frequency, λ = wavelength

1.) f = 100Hz, λ = 0.30m

v = 100 * 0.30 = 30m/s

2) f = 50Hz λ = 0.10m

v = 50 × 0.10 = 5m/s

3) v = 20m/s, λ= 0.5m

f = v / λ

f = 20 / 0.5 = 40Hz

4) v = 80m/s, λ= 0.2m

f = 80/0.2 = 400Hz

5) v = 120m/s, λ = 0.4m

f = 120 / 0.4 = 300Hz

6) v = 340m/s, f = 440Hz

λ = v / f ; 340 / 440 = 0.77m

7) v = 340m/s, f = 880Hz

λ = 340 / 880 = 0.386m

8) v = 250m/s, f = 400

λ = 250 / 400 = 0.625m

9) f = 50Hz, λ = 2m

v = 50 × 2 = 100m/s

10) f = 100Hz, λ = 0.5m

v = 100 × 0.5 = 50m/s

I have a test tomorrow and I can't find the definitions in my book so can you pls help me study by answering the following question? thnx! I will also mark the brainliest.

Answers

Answer:

See explanation

Explanation:

An element is a substance that cannot be chemically converted to another substance or broken down chemically into other substances.

Elements are represented by symbols. The symbol of an element may be the first one or two letters from its English or Latin name. For instance, the symbol of nitrogen is N. This symbol was derived from the first letter of its English name. The symbol for sodium is Na. This was derived from the first two letters of its Latin name, Natrium.

The periodic table is divided into horizontal rows called periods and vertical columns called groups. All members of the same period have the same number of electron shells while all members of the same group have the same number of valence electrons.

Metals are found towards the left hand side of the periodic table while non metals are found towards the right hand side of the periodic table. Metals looses electrons easily while nonmetals accepts electrons easily. Metals are good conductors of heat and electricity while non metals are poor conductors of heat and electricity.Metalloids have properties intermediate between those of metals and non metals and are found at the boarder line between metals and non metals in the periodic table. Metalloids include; silicon, boron, germanium, etc. The electrical conductivity of metalloids increases with temperature while the electrical conductivity of metals decreases with temperature.

Throwing a football is an example of what type of motion ?
a) two-dimensional
b) one-dimensional
c) displacement
d) distance

Answers

The correct answer is A two dimensional
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