No questions found
(a) State two SI base units other than kilogram, metre and second. [1]
(b) Determine the SI base units of resistivity. [3]
(c) (i) A wire of cross-sectional area 1.5 mm2 and length 2.5 m has a resistance of 0.030 Ω.
Calculate the resistivity of the material of the wire in nΩm. [3]
(ii) 1. State what is meant by precision.
2. Explain why the precision in the value of the resistivity is improved by using a micrometer screw gauge rather than a metre rule to measure the diameter of the wire. [2]
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(a) Define velocity. [1]
(b) A ball of mass 0.45 kg leaves the edge of a table with a horizontal velocity v, as shown in Fig. 2.1
The height of the table is 1.25 m. The ball travels a distance of 1.50 m horizontally before hitting the floor.
Air resistance is negligible.
Calculate, for the ball,
(i) the horizontal velocity v as it leaves the table, [3]
(ii) the velocity just as it hits the floor,
magnitude of velocity =$ \text{..................................................ms}^{{-1}}$
angle to the horizontal = $\text{...................................................}^{{\circ}} $[4]
(iii) the kinetic energy just as it hits the floor, [2]
(iv) the loss in gravitational potential energy as it falls from the table to the floor. [2]
(c) Explain why the kinetic energy of the ball in (b)(iii) does not equal the loss of gravitational potential energy in (b)(iv). [1]
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The Young modulus of the material of a wire can be determined using the apparatus shown in Fig. 3.1.
One end of the wire is clamped at C and a marker is attached to the wire above a scale S. A force to extend the wire is applied by attaching masses to the other end of the wire.
The reading X of the marker on the scale S is determined for different forces F applied to the end of the wire. The variation with X of F is shown in Fig. 3.2
(a) The length of the wire from C to the marker for $F = 0$ is 3.50 m. The diameter of the wire is 0.38 mm.
Use the gradient of the line in Fig. 3.2 to determine the Young modulus $E$ of the material of the wire in TPa. [3]
(b) The experiment is repeated with a thicker wire of the same material and length.
State how the range of the force $F$ must be changed to obtain the same range of scale readings as in Fig. 3.2. [1]
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(a) State Newton's first law of motion. [1]
(b) An object A of mass 100 g is moving in a straight line with a velocity of 0.60 m s^{-1} to the right.
An object B of mass 200 g is moving in the same straight line as object A with a velocity of 0.80 m s^{-1} to the left, as shown in Fig. 4.1.
Objects A and B collide. Object A then moves with a velocity of 0.40 m s^{-1} to the left.
(i) Calculate the magnitude of the velocity of B after the collision. [2]
(ii) The collision between A and B is inelastic.
Explain how the collision is inelastic and still obeys the law of conservation of energy. [1]
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(a) Define the $\textit{frequency}$ of a sound wave. [1]
(b) A sound wave travels through air. Describe the motion of the air particles relative to the direction of travel of the sound wave. [1]
(c) The sound wave emitted from the horn of a stationary car is detected with a microphone and displayed on a cathode-ray oscilloscope (c.r.o.), as shown in Fig. 5.1.
The \( y\)-axis setting is \( 5.0 \, \text{mV} \cdot \text{cm}^{-1}\). The time-base setting is \( 0.50 \, \text{ms} \cdot \text{cm}^{-1}\).
(i) Use Fig. 5.1 to determine the frequency of the sound wave. [2]
(ii) The horn of the car sounds continuously. Describe the changes to the trace seen on the c.r.o. as the car travels at constant speed [3]
- directly towards the stationary microphone,
- directly away from the stationary microphone.
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(a) Interference fringes may be observed using a light-emitting laser to illuminate a double slit. The double slit acts as two sources of light. Explain
(i) the part played by diffraction in the production of the fringes, [2]
(ii) the reason why a double slit is used rather than two separate sources of light. [1]
(b) A laser emitting light of a single wavelength is used to illuminate slits $S_1$ and $S_2$, as shown in Fig. 6.1.
An interference pattern is observed on the screen AB. The separation of the slits is 0.48 mm. The slits are 2.4 m from AB. The distance on the screen across 16 fringes is 36 mm, as illustrated in Fig. 6.2.
Calculate the wavelength of the light emitted by the laser. [3]
(c) Two dippers $D_1$ and $D_2$ are used to produce identical waves on the surface of water, as illustrated in Fig. 6.3.
Point P is 7.2 cm from $D_1$ and 11.2 cm from $D_2$. The wavelength of the waves is 1.6 cm. The phase difference between the waves produced at $D_1$ and $D_2$ is zero.
(i) State and explain what is observed at P. [2]
(ii) State and explain the effect on the answer to (c)(i) if the apparatus is changed so that, separately, [2]
- the phase difference between the waves at $D_1$ and at $D_2$ is 180°,
- the intensity of the wave from $D_1$ is less than the intensity of that from $D_2$.
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(a) Define electromotive force (e.m.f.) of a cell.
..........................................................................................................................
..........................................................................................................................[1]
(b) A cell C of e.m.f. 1.50 V and internal resistance 0.200 Ω is connected in series with resistors X and Y, as shown in Fig. 7.1.
The resistance of X is constant and the resistance of Y can be varied.
(i) The resistance of Y is varied from 0 to 8.00 Ω.
State and explain the variation in the potential difference (p.d.) between points A and B (terminal p.d. across C). Numerical values are not required.
..........................................................................................................................
..........................................................................................................................
..........................................................................................................................
..........................................................................................................................[3]
(ii) The resistance of Y is set at 6.00 Ω. The current in the circuit is 0.180 A.
Calculate
1. the resistance of X,
resistance = .............................................................. Ω [2]
2. the p.d. between points A and B,
p.d. = .............................................................. V [2]
3. the efficiency of the cell.
efficiency = .............................................................. [2]
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(a) Describe \textit{two} differences between the decay of a nucleus that emits a $\beta^-$ particle and the decay of a nucleus that emits a $\beta^+$ particle.
1. .................................................................
.................................................................
.................................................................
2. .................................................................
.................................................................
.................................................................
(b) In a simple quark model there are three types of quark. State the composition of the proton and of the neutron in terms of these three quarks.
proton: .................................................................
neutron: .................................................................
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