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
vazorg [7]
4 years ago
9

What is the lateral surface area of a cylinder with height of 7 m and a base diameter of 4 m (to the nearest whole number)?

Physics
1 answer:
yuradex [85]4 years ago
8 0
2×22/7×2×7
44/7×2×7
44×2
88
You might be interested in
How can you tell if one object has more mass than another does, on a planet without gravity
Serhud [2]

an object is more dense if there is more weight in the same area, its because of the amount of particles and the weight of the particles. eg, 1cm cubed of gold would weigh alot more than 1cm cubed polystyrene, so gold is more dense

3 0
3 years ago
Drag and drop the terms at the left to match the appropriate descriptions at the right. ResetHelp Visual acuity Emmetropia Accom
Lubov Fominskaja [6]

Answer: Visual acuity: sharpness of vision.

Myopia: nearsightedness

Refraction: bending of light rays.

Emmetropia: normal vision.

Accommodation: changes the shape of the eye lens to focus light on the retina.

Presbyopia: age-related farsightedness due to loss of elasticity in the lens.

Astigmatism: reduction in visual acuity due to changes in the cornea or lens.

Hyperopia: farsightedness

Myopia and hyperopia are refractive errors of the eye.

Presbyopia occurs in old age people.

Explanation:

Visual acuity: It can be defined as the inability to observe the details of shape of the object. Person loses sharpness in vision.

Myopia: It is a defect in vision in which person is able to observe the near by objects clearly but not able to see the distant objects.

Refraction: It can be defined as the bending of beam of light when it passes through from one substance to another.

Emmetropia: It is a vision without any defect.

Accommodation: It is the ability of the eye to adjust its focal length and adjusting the light on focus.

Presbyopia: It can be defined as the loss of ability of eye to focus on the object. It occurs in old age.

Astigmatism: It is a refractive error in which the eye does not focus light on retina.

Hyperopia: It is also called as farsightedness. Distant objects can be seen clearly but nearby appears blurry.

5 0
3 years ago
A 50-cm-long spring is suspended from the ceiling. A 230g mass is connected to the end and held at rest with the spring unstretc
alukav5142 [94]

Answer:

k = 25.07 N/m

Amplitude = 9 cm

f = 1.66 Hz

Explanation:

Given:

- The original length of the spring L_o = 50 cm

- The mass hanged m = 230 g

- The amount of stretch given 2x = 18 cm @lowest point.

Find:

a. What is the spring constant? (K=)

b. What is the amplitude of the oscillation?

c. What is the frequency of the oscillation?

Solution:

- Make a FBD of the hanging mass, There are two external forces acting on it that is the force of gravity due to its weight and the springs restoring force when its stretched to its lowest point. After hanging the mass on the spring a new equilibrium position is achieved which also causes the spring to stretch. We can apply the Equilibrium conditions at this point in vertical direction as:

                                      k*x - m*g = 0

                                      k = m*g / x

Where, x is the extension of the spring or mean stretch. which 0.5*amplitude (Lowest point). x = 9 cm

                                      k = 0.23*9.81 / 0.09

                                      k = 25.07 N/m

Answer: For part a we have the stiffness of the spring k = 25.07 N/m

- The amplitude of the oscillating motion is the half the amount of total stretch or the amount the spring extends above or below the mean position.

                                       Amplitude = x = 9 cm

- The frequency of any oscillatory motion which can be modeled by SHM can be expressed as:

                                       f = 1 / 2*p*  sqrt ( k / m )

- Plug the values in:                                        

                                       f = 1 / 2*pi* sqrt (25.07 / 0.23 )

                                       f = 1.66 Hz

Answer: For part c the frequency of oscillation is f = 1.66 Hz

           

8 0
3 years ago
Why are microwaves beneficial to use for transmitting information
Darya [45]

Microwaves. Microwave radiation can be used to transmit signals such as mobile phone calls. ... Certain microwave radiation wavelengths pass through the Earth's atmosphere and can be used to transmit information to and from satellites in orbit

5 0
4 years ago
What is the frequency and wavelength, in nanometers, of photons capable of just ionizing nitrogen atoms?
nika2105 [10]

Answer:

The frecuency and wavelength of a photon capable to ionize the nitrogen atom are ν = 3.394×10¹⁵ s⁻¹  and λ = 88.31 nm.

Explanation:It is possible to know what are the frequency and wavelength of a photon capable to ionize the nitrogen atom using the equation of the energy of a photon described below.

E = hc/λ  (1)

Where h is the Planck constant, c is the speed of light and λ is the wavelength of the photon.

But first, it is neccesary to know the ionization energy of the nitrogen atom. The ionization energy is the energy needed to remove an electron from an atom, for the Nitrogen atom it will lose an electron of its outer orbit from the nucleus, farther snuff, so the electric force is weaker. Experimentally, it is known that it has a value of 14.04 eV. This value is easy to found in a periodic table.

So the nitrogen atom will need a photon with the energy of 14.04 eV to remove the electron from its outer orbit.

Replacing the Planck constant, the speed of light and the energy of the photon in the equation 1, the wavelength can be calculated:

λ = hc/E  (2)

Where h = 6.626×10⁻³⁴ J.s and c = 3.00×10⁸ m/s

But the Planck constant can be expressed in electron volts:

1 eV = 1.602 x 10⁻¹⁹ J

h = 6.626x10⁻³⁴ J/1.602x10⁻¹⁹ J . eV .s

h= 4.136x10⁻¹⁵ eV.s

Now, it is convenient to express the speed of light in nanometers:

1nm = 1x10⁻⁹ m

c = 3.00x10⁸ m/ 1x10⁻⁹ m

c = 3x10¹⁷ nm/s

Substituting in equation 2:

λ =  (4.136x10⁻¹⁵ eV.s)(3x10¹⁷ nm/s)/14.04 eV

λ = 1240 eV. nm/ 14.04 eV

λ = 88.31 nm

The frenquency is calculated using the equation 2 in the following way:

E = hν  (3)

Where ν is the frecuency

ν = E/h

ν = 14.04 eV/4.136×10⁻¹⁵ eV.s

ν = 3.394×10¹⁵ s-1

So the frecuency of a photon, capable to ionize the nitrogen atom, will be 3.394×10¹⁵ s⁻¹ and its wavelength 88.31 nm.

4 0
4 years ago
Other questions:
  • Suppose Galileo and his assistant were 1 km apart when Galileo uncovered his lantern to try to measure the speed of light. How l
    12·1 answer
  • How did dalton improve the atomic theory more than 2000 years after democritus's hypothesis about atoms?
    6·1 answer
  • An electron is released from rest at the negative plate of a parallel plate capacitor. The charge per unit area on each plate is
    10·1 answer
  • Rank in order, from largest to smallest, the magnitudes of the electric field at the black dot. A. 2, 1, 3, 4 B. 1, 4, 2, 3 C. 3
    5·1 answer
  • Which major planet has the largest . . .
    6·1 answer
  • A car moving in the positive direction with an initial velocity of 26 m/s slows down at a constant rate of -3 m/s2. What is its
    13·1 answer
  • As an ice cube melts, its molecules
    9·1 answer
  • A cup of mass 0.4 kg with its base radius of 4 cm is kept on a table. Calculate the pressure exerted by the cup on the table.​
    10·1 answer
  • Which of the following compounds has a soapy feel?<br> co3<br> koh<br> nacl<br> hcooh
    10·1 answer
  • A certain toaster has a heating element made of Nichrome wire. When the toaster is first connected to a 120-V source (and the wi
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!