Answer:
A half-life is the time required for one half of the nuclei in a radio- active isotope to decay.
Explanation:
A radio-active isotope is an isotope which undergoes radioactive decay.
Radioactive decay is a spontaneous process in which the nucleus of an atom changes its state (turning into a different nucleus, or de-exciting), emitting radiation, which can be of three different types: alpha, beta or gamma.
The half-life of a radio-active isotope is the time required for half of the nuclei of the initial sample to decay.
The law of radio-active decay can be expressed as follows:
where
N(t) is the number of undecayed nuclei left at time t
N0 is the initial number of nuclei
t is the time
is the half-life
We see that when 
(that means, when 1 half-life has passed), the number of undecayed nuclei left is
So, half of the initial nuclei.
Answer : The correct option is, (D) Velocity includes rate of change and direction.
Explanation :
Speed : Speed is defined as the distance traveled by an object with respect to the time taken. It is a scalar quantity that means it tell us about the magnitude of an object not direction.
Velocity : Velocity is defined as the rate of change of position of an object with respect to the time. It is a vector quantity that means it tell us about the magnitude and direction of an object.
The only difference between the speed and the velocity is that the velocity tell us about magnitude and direction but speed tell us about magnitude only.
Hence, the correct option is, (D) Velocity includes rate of change and direction.
Answer:
When flying the LNAV Approach, the missed approach point (MAP) would be indicated by reaching:
C. the RW30 waypoint.
Explanation:
- In Aviation, LNAV stands for Lateral Navigation. The option a is incorrect as an altitude of 3100 feet refers to the decision altitude not the missed approach point.
- The option b is incorrect as a distance of 1.5 NM to RW30 referring to the Visual descent point (VDP) is 1.5 nautical miles for the Runway (RW) 30 from threshold.
- The option c is correct as Missed approach point is designed to coincide with the runway threshold. The RW 30 way point is referring to the way point to the threshold for the Runway 30.
Apply the combined gas law
PV/T = const.
P = pressure, V = volume, T = temperature, PV/T must stay constant.
Initial PVT values:
P = 1atm, V = 8.0L, T = 20.0°C = 293.15K
Final PVT values:
P = ?, V = 1.0L, T = 10.0°C = 283.15K
Set the PV/T expression for the initial and final PVT values equal to each other and solve for the final P:
1(8.0)/293.15 = P(1.0)/283.15
P = 7.7atm
