A student observes an airplane fly overhead with a constant velocity parallel to
ID: 1432924 • Letter: A
Question
A student observes an airplane fly overhead with a constant velocity parallel to the x-axis at a height of 7.60 x 10^3 m. At time t = 0 the airplane is directly above the student, the vector P0 = 7.60 x 10^3j m describes the position on the airplane with respect to the student. At time t = 30.0 s, the position vector has changed to P_30 = (8.04 x 10^3z + 7.60 x 10^3j m as shown in the figure below. Ignore drag. Determine the magnitude and orientation of the airplane's position vector at t = 45.0 Write down a time-dependent vector Pt that describes the position of the airplane with respect to the student at any time after t = 0.Explanation / Answer
at t=o
xo =0
y0 =7.6*10^3 j
at t =30 s
P30 = (8.04*10^3 i)+(7.6*10^3)j
x30 = 8.04*10^3
From kinematic equaiton along x axis
x -xo = uxt+(1/2)axt^2
8.04*10^3 - 0 = 0+(0.5*a*30*30)
ax = 17.87 m/s^2
(a) at t=45 s
x =xo+(1/2)axt^2 = (0.5*17.87*45*45)
x= 18.1*10^3
P40 = (18.1*10^3)i+(7.6*10^3)j
P40 =10^3((18.1)^2+(7.6)^2)^1/2
Magnitude P40 = 19.63*10^3 m
direction tan(theta) = 7.6/18.1
theta = 22.8 degrees with positive x axis
(b) Pt = (8.935t^2)i+(7.6*10^3)j
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.