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The Language of Physics - A Foundation for University Study - J. Cullerne, A. Machacek (Oxford, 2008)


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- Dynamics is the study of the physical laws of motion.
- (1.2) Figure 1.2 depicts a small portion of the curve (1.1).
- which is of course the area of the trapezium α, β , γ, δ..
- Equation (1.28) is of the form f (v.
- The change in the velocity, say ∆v, of the ball over a time.
- In terms of the Cartesian coordinates x(t) and z(t) the vector r(t) is x(t).
- (a) Show that if one chooses coordinate system for the problem as shown above (x, y), then the equation of the path is.
- The subtraction r 2 − r 1 has the meaning of the relative displacement.
- Calculate the speed of the car..
- The momenta of the three masses in Figure 1.11 are p 1 = m 1 d.
- Determine (a) the acceleration of the system.
- which is the change in momentum of the mass m..
- F is equal to the rate of change of momentum of the mass m:.
- Describe the resulting motion of the 5m mass..
- The initial and final velocities of the spheres are.
- Determine the initial velocities of the particles.
- u, where m and M are the masses of the spheres.
- (b) Show that the speed of the Moon in its orbit is approximately 1.0 km/s..
- This means that the change in potential energy of the object is − mg · s.
- ds = ES cos θ, where S is the total length of the path..
- a · ds is the gain in kinetic energy of the object..
- (e) What is the steepest gradient of the slope?.
- (b) Calculate the value of the loop integral.
- Hint: You need to show that the force on the object is proportional to the distance from the centre of the Earth.
- One part of the object is at position (x, y, z) when its velocity is (u, v, w).
- where ω is the angular velocity of the rotating frame..
- Calculate the acceleration of a point on the rim of the millstone:.
- where m is the mass of the astronaut.
- Looking at the direction ∗ of the force vector.
- The constant e is the eccentricity of the conic section..
- where v is the magnitude of the vector v..
- (a) Show that r∆r sin φ is just the area of the parallelogram ABCD..
- Let us just take stock of the major results:.
- What is the amplitude of the motion?.
- and that the complex amplitude of the combined wave is given by the number A + Be iφ .
- (a) Show that the equation satisfied by the motion of the particle is F = ma.
- (4.21) (f) In this case, show that the solution is of the form.
- Calculate the position of the nodes.
- Derive an expression for the amplitude of the oscillations at position x.
- of the wave at the detector.
- The total disturbance is equal to the sum of the contributing wave displacements:.
- We shall start with a wave of the form y = A cos (ωt − kx + φ.
- where c = ω/k is the speed of the wave.
- Accordingly, all of the interesting motion will be in the vertical direction..
- And so the force is equal to the impedance Z multiplied by the velocity of the waving string.
- The impedance of the material is Z L for x <.
- The actual shape of the wave for x <.
- On the left of the join the force is similarly given by − T ∂(y i +y r )/∂x..
- Q16 Show that the efficiency of the join in terms of power (rather than amplitude) is given by η = 4Z L Z R.
- where E 0 is the amplitude of the wave 1 m from the source..
- Q18 The power output of the Sun is about W.
- 4πD 2 , where P is the total visible power output (luminosity) of the star.
- Assume that all of the current is carried by the copper ions.
- The potential difference of the mains supply is about 230 V.
- What is the ratio of the potential to kinetic energy?.
- terminal of the battery is chosen as the reference point.
- The potential of the reference point (measured with respect to itself) is of course zero..
- Label the negative terminal of the battery (top left point) ‘0 V’..
- The impedance of the component is defined as the complex number Z = V 0 /J 0 .
- (a) Calculate the amplitude of the current..
- (b) Calculate the amplitude of the electron speed in the connecting wire.
- Calculate the amplitude of the voltage..
- Engineers talk of the ‘current leading the voltage’ in a capacitor..
- Engineers talk of the current in an inductor ‘lagging’ the voltage..
- So the voltage drop is in the direction of the current if dI/dt >.
- The diagram is basically a drawing of the complex.
- ‘leading’ it in the case of the capacitor..
- and the phase of the voltage with respect to the current is given by.
- and the overall impedance of the circuit is Series : Z = V.
- and the overall impedance of the circuit is given by.
- The impedance of the capacitor is − i/ωC.
- Accordingly, the impedance of the combi- nation is given by.
- From Figure 5.9 we can see that the magnitude of the voltage will be.
- After (4) we of course return to (1) and the beginning of the next cycle..
- zero and the temperature of the triple point of water.
- Let us suppose that the temperature of the boiler in a steam engine is T A .
- This is an alternative definition of the second law.
- Q7 Estimate the altitude of the mountaineer in Q6.
- Assume that all of the air in the atmosphere is at 0 ◦ C.
- We also presented a justification of the Boltzmann law in the form of a workshop..
- F = d dt P = 0, where P is the total momentum of the system..
- The initial mass of the nth stage, M 0 (n.
- the structural mass of the nth stage, M s (n.
- and the initial mass of the next stage, M 0 (n+1).
- (j) It is found that the pressure difference is proportional to the length of the pipe..
- (a) Calculate the relative uncertainty of the following measurements:.
- How does this compare with the relative uncertainty of the speed?.
- of the body.
- (b) Now assume that the density of the cone in Figure 7.4 is a function of y:.
- 0, which means that (r × p), the angular momentum of the system must be a constant.
- r 4 sin 3 θ dr dθ dϕ, with ρ being the density of the material..
- Workshop: Parallel axes theorem 7.9 155 where R is the radius of the sphere.
- dt , where M is the total mass of the sphere..
- Show that the acceleration of the centre of mass of the sphere is given by a = 5.
- where d is the magnitude of the displacement d (look at the triangle ABC)..
- The eccentricity (e) of the trajectory is related directly to the total energy (E) of the system.
- dQ T = 0 Re-statement of the first law for a reversible process.
- The extremities of the x-values are obtained by setting y = 0:.
- We call this matrix the transpose of the first, R(θ) T.
- where T is the time period of the rotation