Answer:
2000 W
Explanation:
First of all, we need to find the output voltage in the transformer, by using the transformer equation:

where here we have
V1 = 200 V is the voltage in the primary coil
V2 is the voltage in the secondary coil
N1 = 250 is the number of turns in the primary coil
N2 = 500 is the number of turns in the secondary coil
Solving for V2,

Now we can find the power output, which is given by
P = VI
where
V = 400 V is the output voltage
I = 5 A is the output current
Substituting,
P = (400 V)(5 A) = 2,000 W
Given :
The mass of the balloon was 1890 kg and had a volume of 11,430 m3 .
The balloon floats at a constant height of 6.25m above the ground.
To Find :
The density of the hot air in the balloon.
Solution :
We know,
Volume × ( Density of surrounding air - Density of hot air ) = mass
Putting given values in above equation, we get :

Therefore, the density of hot air in the balloon is 1.125 kg m³.
Answer: 5 m
Explanation:
We have the following data:
is the intensity of the sound at 7.5 m from the source
is the distance at which the intensity
was measured
is the intensity of the sound at
from the source
We have to find 
Since the object is radiating the signal uniformly in all directions, we can use the <u>Inverse Square Law for Intensity:</u>

Isolating
:


This is the distance at which the intensity is the "threshold of pain"
Now, we have to substract this value to
to find how much closer to the source can we move:

Answer:
the answer is moss
Explanation:
moss is a low growing plant without roots and thin cell walls
Redox reactions( oxidation-reduction reaction)