An LED is useful because when a current passes through it, it gives out light.
Answer:
A police car with its siren on is driving towards you, and you perceive the pitch of the siren to increase.
Explanation:
In Physics, Doppler effect can be defined as the change in frequency of a wave with respect to an observer in motion and moving relative to the source of the wave.
Simply stated, Doppler effect is the change in wave frequency as a result of the relative motion existing between a wave source and its observer.
The term "Doppler effect" was named after an Austrian mathematician and physicist known as Christian Johann Doppler while studying the starlight in relation to the movement of stars.
<em>The phenomenon of Doppler effects is generally applicable to both sound and light. </em>
An example of the Doppler effect is a police car with its siren on is driving towards you, and you perceive the pitch of the siren to increase. This is so because when a sound object moves towards you, its sound waves frequency increases, thereby causing a higher pitch. However, if the sound object is moving away from the observer, it's sound waves frequency decreases and thus resulting in a lower pitch.
<em>Other fields were the Doppler effects are applied are; astronomy, flow management, vibration measurement, radars, satellite communications etc. </em>
Answer:
D)Not enough information
Explanation:
According to Pascal's principle, the pressure exerted on the two pistons is equal:
Pressure is given by the ratio between force F and area A, so we can write
The force exerted on each piston is just equal to the weight of the corresponding mass: 
, where m is the mass and g is the gravitational acceleration. So the equation becomes
Now we can rewrite the mass as the product of volume, V, times density, d:
We also know that 
So we can further re-arrange the equation (and simplify g as well):
We are also told that block B has bigger volume than block A: 
. However, this information is not enough to allow us to say if the fraction on the right is greater than 1 or smaller than 1: therefore, we cannot conclude anything about the densities of the two objects.
Answer:
The key idea behind the synthesis, processing and application of alloys consist in combining desire qualities from each mineral component in the form of a material.
Explanation:
The key idea behind the synthesis, processing and application of alloys consist in combining desire qualities from each mineral component in the form of a material. For example, steel is the combination of iron, which is ductile but prone to rusting in wet environments, and carbon, which offers high hardness and additional resistence to rusting in wet environments, but is fragile. Hence, steel is more resistant to rusting, ductile as iron and more resistant than iron.
Answer:
46
Explanation:
2900 divided by 63 (2900/63)
- 46.03174603
Rounded to the nearest whole number
is 46.
THE ANSWER IS 46
