We use the kinematic equations,
(A)
(B)
Here, u is initial velocity, v is final velocity, a is acceleration and t is time.
Given,
,
and
.
Substituting these values in equation (B), we get
.
Therefore from equation (A),

Thus, the magnitude of the boat's final velocity is 10.84 m/s and the time taken by boat to travel the distance 280 m is 51.63 s
Answer:
The time rate of change in air density during expiration is 0.01003kg/m³-s
Explanation:
Given that,
Lung total capacity V = 6000mL = 6 × 10⁻³m³
Air density p = 1.225kg/m³
diameter of the trachea is 18mm = 0.018m
Velocity v = 20cm/s = 0.20m/s
dv /dt = -100mL/s (volume rate decrease)
= 10⁻⁴m³/s
Area for trachea =

0 - p × Area for trachea =



⇒

ds/dt = 0.01003kg/m³-s
Thus, the time rate of change in air density during expiration is 0.01003kg/m³-s
Answer:
56400Joules
Explanation:
The quantity of heat required is expressed as;
Q = mL
m is the mass = 25g = 0.025kg
L is the latent heat of vaporization for steam = 2.256×10^6J/kg
Substitute into the formula as shown;
Q = 0.025×2.256×10^6
Q = 56400Joules
Hence the quantity of hear required is 56400Joules
We use the formula: p = E/c where E = hc / λ. hence, p = h/ λ. where h is the Planck's constant: 6.62607004 × 10-34 m2 kg / s and <span>λ is the wavelenght.
</span>
a) p = <span>6.62607004 × 10-34 m2 kg / s / 0.1 x10^-9 m = 6.62607 x 10-24 m kg/s
</span>b) p = 6.62607004 × 10-34 m2 kg / s / 3 x10^-2 m = 2.20869 <span>x 10-32 m kg/s
</span>b) p = 6.62607004 × 10-34 m2 kg / s / 2 x10^-9 m = 3.3130 <span>x 10-25 m kg/s</span>
Answer:
β2= β1+10*f
Explanation:
comparing β2 and β1, it is said that β2 is increased by a factor of f.
for each factor of f, there is a 10*f dB increase.
therefore if the β1 is increases by an intensity of factor f
the new intensity would be β1+ 10*f