(a) No, because the mechanical energy is not conserved
Explanation:
The work-energy theorem states that the work done by the engine on the airplane is equal to the gain in kinetic energy of the plane:
(1)
However, this theorem is only valid if there are no non-conservative forces acting on the plane. However, in this case there is air resistance acting on the plane: this means that the work-energy theorem is no longer valid, because the mechanical energy is not conserved.
Therefore, eq. (1) can be rewritten as

which means that the work done by the engine (W) is used partially to increase the kinetic energy of the airplane (
) and part is lost because of the air resistance (
).
(b) 77.8 m/s
First of all, we need to calculate the net force acting on the plane, which is equal to the difference between the thrust force and the air resistance:

Now we can calculate the acceleration of the plane, by using Newton's second law:

where m is the mass of the plane.
Finally, we can calculate the final speed of the plane by using the equation:

where
is the final velocity
is the initial velocity
is the acceleration
is the distance travelled
Solving for v, we find

Answer:
I = (1.80 × 10⁻¹⁰) A
Explanation:
From Biot Savart's law, the magnetic field formula is given as
B = (μ₀I)/(2πr)
B = magnetic field = (1.0 × 10⁻¹⁵) T
μ₀ = magnetic constant = (4π × 10⁻⁷) H/m
r = 3.6 cm = 0.036 m
(1.0 × 10⁻¹⁵) = (4π × 10⁻⁷ × I)/(2π × 0.036)
4π × 10⁻⁷ × I = 1.0 × 10⁻¹⁵ × 2π × 0.036
I = (1.80 × 10⁻¹⁰) A
Hope this Helps!!!
C the third one i think good luck
Answer:
measure the position every so often with a stopwatch
Explanation:
A possible method of measurement is to place a measuring tape along the path and measure the position every so often with a stopwatch, with this we can make a graph of position against time and by extrapolation find the initial velocity.
This is a method used in measurements of uniform movements of bodies