No questions found
(a) The Young modulus of the metal of a wire is $1.8 \times 10^{11}$ Pa. The wire is extended and the strain produced is $8.2 \times 10^{-4}$. Calculate the stress in GPa.
stress = ...................................................GPa [2]
(b) An electromagnetic wave has frequency 12 THz.
(i) Calculate the wavelength in \(\mu m\).
wavelength = ..................................................\mu m [2]
(ii) State the name of the region of the electromagnetic spectrum for this frequency.
..............................................................................................................[1]
(c) An object B is on a horizontal surface. Two forces act on B in this horizontal plane. A vector diagram for these forces is shown to scale in Fig. 1.1.
A force of 7.5 N towards north and a force of 2.5 N from 30\degree north of east act on B. The mass of B is 750 g.
(i) On Fig. 1.1, draw an arrow to show the approximate direction of the resultant of these two forces. [1]
(ii) 1. Show that the magnitude of the resultant force on B is 6.6 N. [1]
2. Calculate the magnitude of the acceleration of B produced by this resultant force.
magnitude = ............................................. ms\(^{-2}\) [2]
(iii) Determine the angle between the direction of the acceleration and the direction of the 7.5 N force.
angle = ...................................................... \degree [1]
519
545
530
A ball is thrown from A to B as shown in Fig. 2.1
The ball is thrown with an initial velocity $V$ at 60° to the horizontal.
The variation with time $t$ of the vertical component $V_v$ of the velocity of the ball from $t = 0$ to $t = 0.60$ s is shown in Fig. 2.2.
Assume air resistance is negligible.
(a) (i) Complete Fig. 2.2 for the time until the ball reaches B. [2]
(ii) Calculate the maximum height reached by the ball. [2]
(iii) Calculate the horizontal component $V_h$ of the velocity of the ball at time $t = 0$. [2]
(iv) On Fig. 2.2, sketch the variation with $t$ of $V_h$. Label this sketch $V_h$. [1]
(b) The ball has mass 0.65 kg. Calculate, for the ball,
(i) the maximum kinetic energy, [3]
(ii) the maximum potential energy above the ground. [2]
587
577
596
(a) Define \textit{electric field strength}.
.................................................................
................................................................[1]
(b) A sphere $S$ has radius $1.2 \times 10^{-6}$ m and density $930$ kg m$^{-3}$.
Show that the weight of $S$ is $6.6 \times 10^{-14}$ N.
[2]
(c) Two horizontal metal plates are 14 mm apart in a vacuum. A potential difference (p.d.) of 1.9 kV is applied across the plates, as shown in Fig. 3.1.
A uniform electric field is produced between the plates. The sphere $S$ in (b) is charged and is held stationary between the plates by the electric field.
(i) Calculate the electric field strength between the plates.
electric field strength = ............................................ Vm$^{-1}$ [2]
(ii) Calculate the magnitude of the charge on $S$.
charge = ............................................. C [2]
(iii) The magnitude of the p.d. applied to the plates is increased. Explain why $S$ accelerates towards the top plate.
...............................
...............................[2]
587
557
512
(a) Compare the molecular motion of a liquid with
(i) a solid, [2]
(ii) a gas. [1]
(b) (i) A ductile material in the form of a wire is stretched up to its breaking point. On figure 1, sketch the variation with extension $x$ of the stretching force $F$.
(ii) On Figure 2, sketch the variation with extension $x$ of the stretching force $F$ for a brittle material up to its breaking point.
(c) Describe a similarity and a difference between ductile and brittle materials.
579
514
562
A battery of electromotive force (e.m.f.) 12V and internal resistance r is connected in series to two resistors, each of constant resistance X, as shown in Fig. 5.1.
The current I_1 supplied by the battery is 1.2A.
The same battery is now connected to the same two resistors in parallel, as shown in Fig. 5.2.
The current I_2 supplied by the battery is 3.0A.
(a) (i) Show that the combined resistance of the two resistors, each of resistance X, is four times greater in Fig. 5.1 than in Fig. 5.2.
(ii) Explain why I_2 is not four times greater than I_1.
[2]
(iii) Using Kirchhoff’s second law, state equations, in terms of e.m.f., current, X and r, for 1. the circuit of Fig. 5.1,
2. the circuit of Fig. 5.2.
[2]
(iv) Use the equations in (iii) to calculate the resistance X.
X = ...........................................................Ω [1]
(b) Calculate the ratio
$$\frac{\text{power transformed in one resistor of resistance $X$ in Fig. 5.1}}{\text{power transformed in one resistor of resistance $X$ in Fig. 5.2}}.$$
ratio = .............................................................[2]
(c) The resistors in Fig. 5.1 and Fig. 5.2 are replaced by identical 12V filament lamps.
Explain why the resistance of each lamp, when connected in series, is not the same as the resistance of each lamp when connected in parallel.
[2]
523
571
586
(a) State one difference and one similarity between longitudinal and transverse waves.
(b) A laser is placed in front of two slits as shown in Fig. 6.1.
The laser emits light of wavelength $6.3 \times 10^{-7}$ m. The distance from the slits to the screen is 2.5 m. The separation of the slits is 0.35 mm. An interference pattern of maxima and minima is observed on the screen.
(i) Explain why an interference pattern is observed on the screen. [2]
(ii) Calculate the distance between adjacent maxima. [2]
(c) State and explain the effect, if any, on the distance between adjacent maxima when the laser is replaced by another laser emitting ultra-violet radiation.
581
592
512
In the decay of a nucleus of $^{210}_{84} \text{Po}$, an $\alpha$-particle is emitted with energy 5.3 MeV.
The emission is represented by the nuclear equation
$^{210}_{84} \text{Po} \rightarrow^{A}_{B} \text{X} + \alpha + \text{ energy}$
(a) (i) On Fig. 7.1, complete the number and name of the particle, or particles, represented by A and B in the nuclear equation.
(ii) State the form of energy given to the $\alpha$-particle in the decay of $^{210}_{84} \text{Po}$.
.......................................................................................................................[1]
(b) A sample of polonium $^{210}_{84} \text{Po}$ emits $7.1 \times 10^{18}$ $\alpha$-particles in one day.
Calculate the mean power output from the energy of the $\alpha$-particles.
power = ........................................................ W [2]
527
536
548
