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
storchak [24]
2 years ago
5

write an interface downloadable that has a method "geturl" that returns the url of a downloadable object

Engineering
1 answer:
Scrat [10]2 years ago
3 0

Answer:

I want to believe the program is to be written in java and i hope your question is complete. The code is in the explanation section below

Explanation:

import java.util.Date;

public interface Downloadable {

  //abstract methods

  public String getUrl();

  public Date getLastDownloadDate();

 

}

You might be interested in
Explain the process of energy conversion by describing how energy was converted from the windmill design brief. Discuss the diff
cupoosta [38]

Answer:

Wind energy is converted to Mechanical energy  which is then converted in to  electrical energy

Explanation:

In a wind mill the following energy conversions take place

a) Wind energy is converted into Mechanical energy (rotation of rotor blades)

b) Mechanical energy is converted into electrical energy (by using electric motor)

This electrical energy is then used for transmission through electric lines.

6 0
2 years ago
A sinusoidal wave of frequency 420 Hz has a speed of 310 m/s. (a) How far apart are two points that differ in phase by π/8 rad?
Olin [163]

Answer:

a) Two points that differ in phase by π/8 rad are 0.0461 m apart.

b) The phase difference between two displacements at a certain point at times 1.6 ms apart is 4π/3.

Explanation:

f = 420 Hz, v = 310 m/s, λ = wavelength = ?

v = fλ

λ = v/f = 310/420 = 0.738 m

T = periodic time of the wave = 1/420 = 0.00238 s = 0.0024 s = 2.4 ms

a) Two points that differ in phase by π/8 rad

In terms of the wavelength of the wave, this is equivalent to [(π/8)/2π] fraction of a wavelength,

[(π/8)/2π] = 1/16 of a wavelength = (1/16) × 0.738 = 0.0461 m

b) two displacements at times 1.6 ms apart.

In terms of periodic time, 1.6ms is (1.6/2.4) fraction of the periodic time.

1.6/2.4 = 2/3.

This means those two points are 2/3 fraction of a periodic time away from each other.

1 complete wave = 2π rad

Points 2/3 fraction of a wave from each other will have a phase difference of 2/3 × 2π = 4π/3.

8 0
3 years ago
The most important element of green construction is that it is a(n) __________ approach to building. *
madam [21]
Environmentally friendly


Since it focuses on are sustainable and efficient with and are made with the future in mind.
5 0
3 years ago
Sandwich materials typically use a high density core with non-structural cover plates. a)True b)- False
Lorico [155]

Answer: False

Explanation: Sandwich materials are usually in composite material form which has a fabrication of two thin layers which are stiff in nature and have  light weighing and thick core .The construction is based on the ratio that is of stiffness to the weight .Therefore, the density of the material in the core is not high and are only connected with the skin layer through adhesive .So the given statement is false that sandwich materials typically use a high density core with non- structural cover plates.

4 0
3 years ago
Use phasor techniques to determine the impedance seen by the source given that R = 4 Ω, C = 12 μF, L = 6 mH and ω = 2000 rad/sec
Zielflug [23.3K]

Answer:

Z = 29.938Ω ∠22.04°

I = 2.494A

Explanation:

Impedance Z is defined as the total opposition to the flow of current in an AC circuit. In an R-L-C AC circuit, Impedance is expressed as shown:

Z² = R²+(Xl-Xc)²

Z = √R²+(Xl-Xc)²

R is the resistance = 4Ω

Xl is the inductive reactance = ωL

Xc is the capacitive reactance =

1/ωc

Given C = 12 μF, L = 6 mH and ω = 2000 rad/sec

Xl = 2000×6×10^-3

Xl = 12Ω

Xc = 1/2000×12×10^-6

Xc = 1/24000×10^-6

Xc = 1/0.024

Xc = 41.67Ω

Z = √4²+(12-41.67)²

Z = √16+880.31

Z = √896.31

Z = 29.938Ω (to 3dp)

θ = tan^-1(Xl-Xc)/R

θ = tan^-1(12-41.67)/12

θ = tan^-1(-29.67)/12

θ = tan^-1 -2.47

θ = -67.96°

θ = 90-67.96

θ = 22.04° (to 2dp)

To determine the current, we will use the relationship

V = IZ

I =V/Z

Given V = 12V

I = 29.93/12

I = 2.494A (3dp)

7 0
3 years ago
Other questions:
  • The Stefan-Boltzmann law can be employed to estimate the rate of radiation of energy H from a surface, as in
    7·1 answer
  • A water pump delivers 6 hp of shaft power when operating. The pressure differential between the outlet and the inlet of the pump
    9·1 answer
  • A 55-μF capacitor has energy ω (t) = 10 cos2 377t J and consider a positive v(t). Determine the current through the capacitor.
    12·1 answer
  • Lately, you have noticed some repetitive stress in your wrist. Which sign is most likely the cause of that stress and pain?
    7·1 answer
  • Tech A says that in some cases, the electronic brake control module can be programmed with a new tire size to restore proper ele
    7·1 answer
  • Fluorescent troffers are a type of _ lighting fixture
    6·1 answer
  • A cylindrical specimen of some metal alloy having an elastic modulus of 124 GPa and an original cross-sectional diameter of 4.2
    13·1 answer
  • A total of 245 kip force is applied to a set of 10 similar bolts. If the spring constant of each bolt is 0.4 Mlb/in and that of
    9·1 answer
  • Please look at the attachments and help me with these questions
    7·1 answer
  • Two technicians are discussing relays. Technician A says that relays can fail because the relay winding is open. Technician B sa
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!