PHYS1300 MID-TERM PAPER Maths 2 2020/2021
Hello, dear friend, you can consult us at any time if you have any questions, add WeChat: daixieit
PHYS130001
MID-TERM PAPER
Maths 2
Semester Two 2020/2021
1. By what percentage does the force due to gravity on a climber change when climbing from the bottom to the top of Mt. Everest? Use the following values: mass of the Earth M = 6 × 1024 kg, mass of the climber m = 70 kg, radius of the Earth R = 6370 km, height of Mt. Everest ∆r = 8850 m. Work out the answer in two ways:
● Put the two values of r (R, and R + ∆r) into the expression for the gravitational force F , and find the percentage difference × 100%.
● Use the first two terms of the binomial expansion to show that ~ , and evaluate the percentage difference this way.
Does the binomial expansion provide a reasonable estimate of the answer? [10 Marks]
2. Sketch the function f(t) which is defined over the range -π < t < π by:
f = ,0(1)
if - π < t < 0
if 0 < t < π.
State whether f(t) is odd, even, or neither, and explain the reasoning behind your answer. Find the Fourier coefficients, a0 , an and bn , and hence find the Fourier series that describes the function. [10 Marks]
3. The approximate equation for a frictionless pendulum swinging with small amplitude is:
d2 θ
where θ is the angle of inclination from the vertical. The pendulum is held at rest at an angle of π/12 at t = 0 and then released. Solve the 2nd order differential equation subject to these initial conditions.
When the same pendulum is driven with a force F (t) = cos 3t, the equation becomes:
d2 θ
What is the general solution of this differential equation given the same initial condi- tions as above? [10 Marks]
4. Sketch the area between the curves defined by y = 3 - 2x, y = x2 and y = 0, for positive x. What is the mass of a plate of the same shape and area whose surface density varies as x? [10 Marks]
Total 40 marks
2022-05-19