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
To solve this problem it is necessary to apply the concepts related to Sound Intensity. The unit most used in the logarithmic scale is the decibel and mathematically this is expressed as

Where,
= Sound intensity level in decibels
I = Acoustic intensity on the linear scale
Hearing threshold
According to the values, the total intensity is 32 times the linear intensity and the value in decibels is 83dB
So:




Therefore the sound intensity due to one person is 67.948dB
Answer:
c
Explanation:
because it is made out of metel
Answer:
<em>0.25</em>
Explanation:
According to newtons law of motion
\sum F_x = ma
F_f = ma
nR = ma
nmg = ma
ng = a
n = a/g
g is the acceleration due to gravity
Given
a = 2.42m/s²
g = 9.8m/s²
Substitute into the formula;
n = 2.42/9.8
n = 0.25
<em>Hence the coefficient of kinetic friction is 0.25</em>
<em></em>
Answer:
Explanation:
Let the velocity after the 4 gram pencil strikes is v .
kinetic energy of the combination = 1/2 m v²
= .5 x ( 4 + 221 ) x 10⁻³ x v² = work done by friction
friction force acting on the combination = 225 x10⁻³x .325 x 9.8 = .7166 N
work done by friction
= .7166 x .119 = .085 J
.5 x 225 x 10⁻³ v² = .085
v² = .085 / .1125 = .7555
v = .8692 m = 86.92 cm /s
Velocity of combination after collision = 86.92 cm /s
Let velocity of pencil before collision be V
Applying law of conservation of momentum at the time of collision ,
4 x V = 225 x 86.92
V = 4889.25 cm / s
= 48.9 m /s .