Answer:
angle of refraction is the same as angle of incidence
Explanation:
Answer
given,
Power output of loud train = 100 W
Distance of intensity level from train= 100 m
I₀ = 10⁻¹² W/m²
Intensity of sound = ?
we know,
Intensity level
= 
= 
= 
= 89 dB
Answer:
Explanation:
If one assume that each turn is like a strand of electromagnet, which can then be added up. Therefore, increase in the number of turns will yield to increase in the magnetic strength. Also if the current increases, then there will be increase in the magnetic field strength.
From Ohm's law
V = IR
I = V/R
That is a direct increase in voltage will lead to increase in current.
Increase the voltage of the battery and increases the number of turns of the coil. Will suit the situation
The first rule of vectors is that the horizontal and vertical components are separate. Disregarding air resistance, the only thing we have to worry about is gravity.
The appropriate suvat to use for the vertical component is v = u +at
I will take a to be -9.81, you may have to change it to be 10 if your qualification likes g to be 10.
v = 30 + (-9.81x2)
v = 30 - 19.62
=10.38m/s
Therefore we know that after 2.0 s the vertical component will be 10.38ms^-1, ie 10m/s as the answers given are all to 2sf.
The horizontal component is completely separate to the vertical component and since there is no air resistance, it will remain constant throughout the projectiles trajectory. Therefore it will remain at 40ms^-1.
Combining this together we get:
(1) vx=40m/s and vy=10m/s
You said that she's losing 1.9 m/s of her speed every second.
So it'll take
(6 m/s) / (1.9 m/s²) = 3.158 seconds (rounded)
to lose all of her initial speed, and stop.
