# 物理基础1A| Physics 1A: Foundations PHYS08016代写

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This is an introductory-level course, covering the classical physics of kinematics, dynamics, oscillations, forces and fields, and touching on aspects of contemporary physics, including relativity and chaos. The course is designed for those with qualifications in physics and mathematics at SCE-H level or equivalent.

During an IFR flight, a passenger looks out the window while relaxing in his seat. He observes a turn and estimates the bank angle to be $30^{\circ}$. At the same time, the passenger observes the free surface of the orange juice in his glass: it is parallel to the tray.
a) The passenger assumes the turn being flown as a rate one turn. Explain the term rate one turn. Why is it correct to assume a rate one turn.
b) The passenger assumes the turn being flown as a coordinated turn. Explain the term coordinated turn. Why is it correct to assume a coordinated turn.
c) Calculate the aircraft’s true airspeed.

a) A rate one turn is a turn with a heading change of $180^{\circ}$ in 60 seconds. During IFR flights turns are performed as rate one turns.
b) In a coordinated turn (correctly banked turn)

• the lift force lies in the aircraft plane of symmetry,
• the ball in the turn and slip indicator is centered,
• there is no acceleration along the $y$-axis of the aircraft.
This phenomenon is also shown by the free surface of the orange juice in the glass which is parallel to the tray.
c) $\tan \Phi=\frac{V \cdot \Omega}{g}$
$$V=\frac{g}{\Omega} \cdot \tan \Phi=\frac{9.81 \mathrm{~m} \cdot 60 \mathrm{~s}}{\mathrm{~s}^{2} \cdot \pi} \cdot \tan 30^{\circ}=108.2 \frac{\mathrm{m}}{\mathrm{s}}=210 \mathrm{kt}$$
Answer: The aircraft’s true airspeed is $210 \mathrm{kt}$.

## FINM2001 COURSE NOTES ：

The category of effect of a failure is judged to be hazardous. Following $A C J N o$. 1 . to $J A R$ $25.1309$
a) What is the largest permissible failure probability?
b) What is the mean time to failure $M T T F$ ?
Solution
$F(t) \quad$ probability of failure,
$\lambda \quad$ failure rate
MTTF mean time to failure
FH flight hour
a) hazardous : $F(t=1 \mathrm{FH}) \leq 10^{-7}$
b) For small probabilities of failure: $\quad \lambda \approx F / t=10^{-7} \cdot \frac{1}{\mathrm{FH}}$
$$\mathrm{MTTF}=1 / \lambda=\frac{1}{10^{-7}} \mathrm{FH}=10000000 \mathrm{FH}$$
Answer: If a failure has a hazardous effect, the mean time to this failure may not be less than $10000000 \mathrm{FH}$.