Answer:
ωi = 15.4 rev/sec
Explanation:
Since the movement of the fan is rotating, we are thus dealing with Rotational motion. In rotational motion, for angular speed to take place also means angular acceleration is also occurring.
angular acceleration = α = (change in speed)/(change in time)
angular acceleration = α = Δw/Δt = (ω - ωi) /(t- t₀) ..........(equation 1)
α = (ω -ωi) /(t- 0)
α = (ω-ωi) /t
ωi = ω - αt ......................................(equation 2)
where ωi is the initial angular speed.
We replace the values for ω, t and α
ωi = 105 rad/sec - ( 4.4 rad/sec² )(1.85s) = 96.86 rad/s = 15.415747788 rev/sec
Answer:
An electric motor is a device that changes electrical energy into mechanical energy. This change occurs due to the interaction between the magnetic field of magnets and the magnetic field due to the electric current in the loop. The interaction between the two produces a torque that makes the loop rotate on a shaft.
Answer:
First, as you may know, the light travels at a given velocity.
In vaccum, this velocity is c = 3x10^8 m/s.
And we know that:
distance = velocity*time
Now, if some object (like a star ) is really far away, the light that comes from that star may take years to reach the Earth.
This means that the images that the astronomers see today, actually happened years and years ago (So the night sky is like a picture of the "past" of the universe)
Also, for example, if an astronomer sees some particular thing, he can apply a model (a "simplification" of some phenomena that is used to simplify it an explain it) and with the model, the scientist can infer the information of the given thing some time before it was seen.
By definition, acceleration is the change in velocity per change of time. As time passes by, the time increases in value. So, when the acceleration is decreasing while the time is increasing, then that means that the change of velocity is also decreasing with time. So, optimally, the initial velocity and the velocity at any time are very relatively close to each other,
Answer:
B
Explanation:
Gravitational Energy is the energy of position or place. A rock resting at the top of a hill contains gravitational Potential energy. Hydropower, such as water in a reservoir behind a dam, is an example of gravitational potential energy.