Answer:
Speed = 3 [km/h]
Explanation:
To solve this problem we must use the definition of speed which relates the distance traveled for a while.
Distance = 1.5 [km] = 1500 [m].
time = 0.5 [hr] = 1800 [s]
Speed = Distance/time
Speed = 1.5/0.5
Speed = 3 [km/h] or 1500/1800 = 0.8333[m/s]
Answer:
Power = 124.50 W
Explanation:
Given that:
The Sound intensity of a speaker output is 102 dB
and the distance r = 25 m
For the intensity of sound,

where;
the threshold of hearing 



I = 0.01585 W/m²
If we recall, we know remember that ;
Power = Intensity × A
rea
Power = 0.01585 W/m² × 4 × 3.142 × (25 m)²
Power = 124.50 W
Answer:
Therefore the the highest frequency is 620Hz and lowest frequency is 580Hz
Explanation:
Given data
Source Frequency fs=600Hz
Length r=1.0m
RPM=100 rpm
The speed of the generator is calculated as:

Substitute the given values

For approaching generator the frequency is calculated as:

On the other hand,for the receding generator,Doppler's effect is expressed as:

Therefore the the highest frequency is 620Hz and lowest frequency is 580Hz
<span>I believe it's insulation.</span>
The rule that is used to get the strength of magnetic field at the center of solenoid (B) is:
B = <span>µ x n x I where:
</span>µ is the permeability of the medium where the solenoid is based. In this problem, the medium is air which means that µ = <span>µ </span><span>o = 4 pi x 10^-7 Tm/A
</span>I is the current passing (I = 4 amperes)
n is the number of turns per unit length (5000 turns)
Substituting in the mentioned equation, we find that:
B = 4 x 3.14 x 10^-7 x 5000 x 4 = 25.132 mT