Answer:
B.
Explanation:
One of the ways to address this issue is through the options given by the statement. The concepts related to the continuity equation and the Bernoulli equation.
Through these two equations it is possible to observe the behavior of the fluid, specifically the velocity at a constant height.
By definition the equation of continuity is,

In the problem
is
, then


<em>Here we can conclude that by means of the continuity when increasing the Area, a decrease will be obtained - in the diminished times in the area - in the speed.</em>
For the particular case of Bernoulli we have to


For the previous definition we can now replace,


<em>Expressed from Bernoulli's equation we can identify that the greater the change that exists in pressure, fluid velocity will tend to decrease</em>
The correct answer is B: "If we increase A2 then by the continuity equation the speed of the fluid should decrease. Bernoulli's equation then shows that if the velocity of the fluid decreases (at constant height conditions) then the pressure of the fluid should increase"
Answer:
50000 N
Explanation:
From the question given above, the following data were obtained:
Mass (m) of bullet = 0.050 kg
velocity (v) = 400 m/s
Distance (s) = 0.080 m
Force (F) =?
Next, we shall determine the acceleration of the bullet. This can be obtained as follow:
Initial velocity (u) = 0 m/s
Final velocity (v) = 400 m/s
Distance (s) = 0.080 m
Acceleration (a) =?
v² = u² + 2as
400² = 0 + (2 × a × 0.08)
160000 = 0 + 0.16a
160000 = 0.16a
Divide both side by 0.16
a = 160000 / 0.16
a = 1×10⁶ m/s²
Finally, we shall determine the force exerted by the bullet on the target. This can be obtained as follow:
Mass (m) of bullet = 0.050 kg
Acceleration (a) of bullet = 1×10⁶ m/s²
Force (F) =?
F = ma
F = 0.050 × 1×10⁶
F = 50000 N
Thus, the bullet exerted a force of 50000 N on the target.
Answer:
(a) Eₐ = 6.36 J/s
(b) Eₐ = 4.64 J/s
Explanation:
Stefan-Boltzmann law: States that the total energy per second radiated or absorbed by a black body is directly proportional to the absolute temperature.
Using, Stefan-Boltzmann equation
Eₐ =eσAT⁴ ................ Equation 1
where Eₐ = Radiant energy absorbed per seconds, e = emissivity, σ = stefan - boltzman constant, A = Surface area. and T = temperature in kelvin
(a) Where e = 0.89, σ = 5.67 ×10⁻⁸ watt/m²/K⁴, A = 140 cm² = 140 cm²(m²/10000cm²) = 0.014 m², T = 35 °C = (35 + 273) K = 308 K.
Applying these values in equation 1 above,
Eₐ = 0.89 × 5.67 ×10⁻⁸ × 0.014 × (308)⁴
Eₐ =6.36 J/s
(b) when e = 0.65,
∴ Eₐ = 0.65 × 5.67 × 10⁻⁸ × 0.014 × (308)⁴
Eₐ = 4.64 J/s
Answer:
A : A restoring force acts on an object in simple harmonic motion that is directed in the same direction as the object's displacement.
Explanation:
Statement A is the false one:
A : A restoring force acts on an object in simple harmonic motion that is directed in the same direction as the object's displacement. --> FALSE. The restoring force in the simple harmonic motion is given by

where
k is the spring constant
x is the displacement of the system, measured with respect to the equilibrium position
As we can notice from the equation, there is a negative sign in front of (kx): this means that the force, F, and the displacement, x, have opposite directions. In fact, the restoring force of a simple harmonic oscillator always acts to restore the equilibrium position, therefore it acts in the opposite direction as that of the displacement.
Answer:
b) to produce electrical charges;
Explanation:
Electrical generators are used in a circuit to produce electrical charges. The flow of these charges actually produces electrical energy in a circuit which is needed and essential to power devices and gadgets.
A generator uses mechanical energy through the movement of its parts to produce electrical energy. The flow of electrons streams produces the electrical energy which helps to produce power.
A generator works on the basis of electromagnetic induction using the movement of electric charges.