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
Mrrafil [7]
3 years ago
15

If 35 J of work was performed in 70 seconds, how much power was used to do this task?

Physics
1 answer:
Irina18 [472]3 years ago
5 0
P = w \times delta \: T
P = Power
W = Work
Delta T = Change of Time

So:
P = 35 Joules
Delta T = 70 secs
W = ?

P = 35 \div 70 \\ P = 0.5 \: watts

* Joule/Sec = Watt

Answer: The power used to do this task was 0.5 Watts.
You might be interested in
Describe how the number of photoelectrons emitted from a metal plate in the photoelectric effect would change if the following o
andrew-mc [135]

Answer:

a) True. The number of photoelectrons is proportional to the amount (intensity) of the incident beam. From the expression above we see that threshold frequency cannot emit electrons.

b)   λ = c / f

Therefore, as the wavelength increases, the frequency decreases and therefore the energy of the photoelectrons emitted,

c)  threshold energy

        h f =Ф

Explanation:

It's photoelectric effect was fully explained by Einstein by the expression

       Knox = h f - fi

Where K is the kinetic energy of the photoelectrons, f the frequency of the incident radiation and fi the work function of the metal

a) True. The number of photoelectrons is proportional to the amount (intensity) of the incident beam. From the expression above we see that threshold frequency cannot emit electrons.

b) wavelength is related to frequency

         λ = c / f

Therefore, as the wavelength increases, the frequency decreases and therefore the energy of the photoelectrons emitted, so there is a wavelength from which electrons cannot be removed from the metal.

c) As the work increases, more frequency radiation is needed to remove the electrons, because there is a threshold energy

        h f =Ф

7 0
3 years ago
Does anyone know the answer to all of these questions
Rasek [7]

Answer:

i don't understand the hw

5 0
3 years ago
There is a uniform magnetic field of magnitude B, pervading all space, perpendicular to the plane of rod and rails. The rod is r
Charra [1.4K]

The right hand rule to find the direction of the magnetic field for a falling bar is:

  • The charge is positive the magnetic field is outgoing, horizontally and towards us.
  • The charge of the bar is negative, the magnetic field is incoming, that is horizontal away from us.

The magnetic force is given by the vector product of the velocity and the magnetic field.

        F = q v x B

Where the bolds indicate vectors, F is the force, q the charge on the particle, v the velocity and B the magnetic field.

In the vector product, the vectors are perpendicular, which is why the right-hand rule has been established, see attached:

  • The thumb points in the direction of speed.
  • Fingers extended in the direction of the magnetic field.
  • The palm is in the direction of the force if the charge is positive and in the opposite direction if the charge is negative.

They indicate that the bar is dropped, therefore its speed is vertical and downwards, it moves to the left therefore this is the direction of the force, we use the right hand rule, the magnetic field must be horizontal, we have two possibilities:

  • If the charge is positive the magnetic field is outgoing, horizontally and towards us.
  • If the charge of the bar is negative, the magnetic field is incoming, that is, horizontal away from us

In conclusion using the right hand rule we can find the direction of the magnetic field for a falling bar is:

  • The charge of the bar is negative, the magnetic field is incoming, that is horizontal away from us.
  • The charge is positive the magnetic field is outgoing, horizontally and towards us.

Learn more about the right hand rule here:  brainly.com/question/12847190

6 0
3 years ago
What source of energy is responsible for the water cycle
Eduardwww [97]
Water? The sun. I DUNNO I FEEL BAD :(
7 0
2 years ago
11. Trait theory claims that
svetoff [14.1K]
A. people from the same location share the same personality type.
3 0
2 years ago
Other questions:
  • The force that pushes against something traveling through a fluid is called
    14·1 answer
  • A 0.145 kg baseball is thrown with a velocity of 40 m/s. What is the baseball's momentum?
    12·1 answer
  • When all parts of a circuit are composed of conducting materials, the circuit is said to be
    6·1 answer
  • What are some properties of transverse waves?
    13·1 answer
  • The process by which atoms are arranged to form a material with a crystal shape is called
    9·2 answers
  • A lawn roller in the form of a solid uniform cylinder is being pulled horizontally by a horizontal force B applied to an axle th
    13·1 answer
  • An airplane pilot wishes to fly due west. A wind of 80.0 km/h (about 50 mi/h) is blowing toward the south. (a) If the airspeed o
    13·1 answer
  • A light bulb is supplied with 100 J of energy each
    12·1 answer
  • How far can you get away from your little brother with a paintball marker if you can travel at 3 m/s and you have 15s before he
    13·1 answer
  • Kayla and her friends are setting up chairs for a school play each row will contain the same number of chairs Kayla knows that t
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!