Answer:
string's damping is 1.03676
Explanation:
given data
sound level = 9.0 dB
time = 1 sec
to find out
string's damping
solution
we will apply here formula for string damping (b) that is
A(t) = A × 
...................1
we know here I ∝ A² so
√I(t) = √I ×
√I(t) / √I = .....................2
we know sound level decreases 9 dB i.e ΔdB = 9
so we can write
ΔdB = 10 log ( I(t) / I)
9 = 10 log ( I(t) / I)
I(t) / I = 
I(t) / I = 0.1258
and
√I(t) / I) = √0.1258 = 0.3546 .......................3
from equation 2 and 3 we get
0.3546 =
take ln both side
-bt = ln 0.3546
here we know t is 1 sec
so
- b = - 1.03676
b = 1.03676
so here string's damping is 1.03676
Answer:
The speed of ejection is 
Solution:
As per the question:
Magnetic field density, B = 0.4 T
Density of the material in the sunspot, 
Now,
To calculate the speed of ejection of the material, v:
The magnetic field energy density is given by:
This energy density equals the kinetic energy supplied by the field.
Thus
where
m = mass of the sunspot in 
= 
Answer:
1. 579 x 10 ^-22N
Explanation:
F = kq1q2/r^2
= 9.0 x 10^9 x 5.67 x 10^-18 x 3.79 x 10^-18/ (3.5 x 10^-2)^2
= 1. 579 x 10 ^-22N
Answer:
The effect of lowering the condenser pressure on different parameters is explained below.
Explanation:
The simple ideal Rankine cycle is shown in figure.
Effect of lowering the condenser pressure on
(a). Pump work input :- By lowering the condenser pressure the pump work increased.
(b) Turbine work output :- By lowering the condenser pressure the turbine work increased.
(c). Heat supplied :- Heat supplied increases.
(d). Heat rejected :- The heat rejected may increased or decreased.
(e). Efficiency :- Cycle efficiency is increased.
(f). Moisture content at turbine exit :- Moisture content increases.
Answer:
0.018 J
Explanation:
The work done to bring the charge from infinity to point P is equal to the change in electric potential energy of the charge - so it is given by
where
is the magnitude of the charge
is the potential difference between point P and infinity
Substituting into the equation, we find
