The diagram above represents the trajectory of a projectile with an initial velocity U. Calculate the time taken to reach the maximum height. (Take g as acceleration due to gravity)
Απάντηση
(E)
Usinθ/g
3
What change in velocity would be produced on a body of mass 4kg if a constant force of 16 N acts on it for2 s?
Απάντηση
(C)
8.0 ms-1
4
Which of the following statements about solid friction is/are correct? I. Friction depends on the nature of the surfaces in contact II. Friction depends on the area of contact III. Friction always acts in the direction of motion.
Απάντηση
(A)
I only
5
A body accelerates uniformly from rest at the rate of 3 m/s\(^2\) for 8 seconds. Calculate the distance covered by the body during the acceleration?
Απάντηση
(E)
96m
6
Which of the following has the same unit as the moment of a force?
Απάντηση
(C)
Work
7
Solid weighs 0.040 N in air and 0.024 N when fully immersed in a liquid of density 800 kg m-3. What is the volume of the solid? (g = 1Oms2)
Απάντηση
(A)
2.0 x 10-6m3
8
Which of the following will reduce the frequency of oscillation of a simple pendulum?
Απάντηση
(C)
Increasing the length of the string
9
A force of 20 N applied parallel to the surface of a horizontal table, is just sufficient to make a block of mass 4kg move on the table. Calculate the coefficient of friction between the block and the table. (g = 10ms2)
Απάντηση
(C)
0.50
10
A barometer can be used in determining the I. height of a mountain II. depth of a mine III. dew point. Which of the following is/are correct?
Απάντηση
(D)
I and II only
11
A body of mass 5kg falls from a height of 10m above the ground. What is the kinetic energy of the body just before it strikes the ground? (Neglect energy losses and take gravity as 10ms^2)
Απάντηση
(D)
500J
12
Steel bars, each of length 3.0 m at 28°C, are to be used for constructing a rail line. If the linear expansivity of steel is 1.0 x 10-5°C, what is the safety gap that must be left between successive bars if the highest temperature expected is 40oC?
Απάντηση
(D)
3.6 x 10-2cm
13
Which of the following statements is/are correct? I. Pure water freezes at 0oC under normal pressure ll. Water has its highest density at 4oC. III. The volume at 4oC,
Απάντηση
(C)
I and II only
14
A given mass of gas at a temperature of 30°C is trapped in a tube of volume V. Calculate the temperature of the gas when the volume is reduced to two-third of its original value by applying a pressure twice the original value.
Απάντηση
(C)
131oC
15
Which of the following colours of surfaces will radiate heat energy best?
Απάντηση
(C)
Black
16
A gas which obeys Charles’ law exactly has a volume of 283cm3 at 10oC. What is its volume at 30oC?
Απάντηση
(C)
303cm3
17
Which of the following best explains why a person suffers a more severe burn when his skin is exposed to steam than when boiling water pours on his skin?
Απάντηση
(B)
Steam possesses greater heat energy per unit mass than boiling water
18
A small circular membrane is 10cm below the surface of a pool of mercury when the barometric height is 76 cm of mercury. If the density of mercury is 13600\(kgm^{-3}\), what is the pressure on the membrane in \(Nm^{-2}\)? \((g =10ms^{-2})\)
Απάντηση
(C)
1.17x105Nm-2
19
Which of the following instruments is used to measure relative humidity?
Απάντηση
(E)
Hygrometer
20
A metal of mass 1.5 kg was heated from 27oC to 47oC in 4 minutes by a boiling ring of 75 W rating. Calculate the specific heat capacity of the metal, (Neglect heat losses to the surrounding)
Απάντηση
(B)
6.0 X102J kg-10C-1
21
A ray of light strikes a plane mirror at an angle of incidence i. Determine in terms of i the angle of deviation of the ray after reflection from the mirror.
Απάντηση
(E)
180o - 2i
22
Images formed by a convex mirror are always
Απάντηση
(C)
erect, virtual and diminished
23
Which of the following statements is not correct for a light ray passing through a rectangular glass block which is surrounded by air? It
Απάντηση
(A)
suffers a displacement at the point of emergence
24
In an experiment to measure1 the focal length f of a converging lens object distances u and corresponding image distance were measured and 1/u plotted against 1/v to obtain the graph illustrated. How would f be determined from this graph?
Απάντηση
(E)
f = reciprocal of the intercept on either axes
25
The image of a pin formed by a diverging lens of focal length 10cm is 5cm from the lens. Calculate the distance of the pin from the lens
Απάντηση
(B)
3.3cm
26
As an object is moved close to the focus of a converging lens from infinity its image I. moves closer to the lens II. moves away from the lens. III. Remains the same size. IV becomes smaller. Which of the statements above is/are correct?
Απάντηση
(E)
II only
27
A real image of an object fom1ed by a converging lens of focal length 15cm is three times the size of the object. What is the distance of the object from the lens?
Απάντηση
(C)
20cm
28
The eye defect illustrated in the diagram above can be corrected by a
Απάντηση
(C)
diverging lens
29
When an astronomical telescope is in normal adjustment, the focal length of the objective lens is 50cm and that of the eyepiece is 2.5om. What is the distance between the lenses?
Απάντηση
(D)
52.5cm
30
Which of the following is used for controlling the amount of light entering the eye?
Απάντηση
(C)
Iris
31
The angle of deviation of light of various colours passing through a glass prism decreases in the order of
Απάντηση
(A)
blue orange and red
32
The change of the direction of a wavefront as a result of a change in the velocity of the wave in another medium is called
Απάντηση
(A)
refraction
33
The diagram above shows a waveform in which energy is transferred from A to B in a time of 2.5 x 10-3s. Calculate the frequency of the wave
Απάντηση
(B)
1.0 x 103Hz
34
Which of the following radiations have the highest frequency?
Απάντηση
(C)
X-rays
35
How far from a cliff should a boy stand in order to hear the echo of his clap 0.9s later? (Speed of sound in air = 330 ms-1)
Απάντηση
(C)
148.50m
36
Which of the following waves are longitudinal waves? l. Ripples on the surface of water II. Waves produced by a tuning fork vibrating in air III. Light waves
IV. Waves produced by a flute
Απάντηση
(D)
II and IV only
37
Which of the following statements is not true?
Απάντηση
(C)
the loudness of sound is determined by its frequency
38
A pipe closed at one end is 1.0m long. The air in the pipe is set into vibration and a fundamental note of frequency 85Hz is produced. Calculate the velocity of sound in the air. (Neglect end correction).
Απάντηση
(A)
340.0ms-1
39
The diagram above shows the magnetic field around a bar magnet which has its N-pole pointing north. The neutral points in the field are likely to occur at
Απάντηση
(D)
7 and 8
40
A negatively charged rod is brought near the cap of a gold-leaf electroscope. The cap is earthed momentarily while the rod is near to it. The rod is then removed. Which of the following is correct?
Απάντηση
(C)
The cap and the leaves will be positively charged
41
Calculate the rate at which energy is used up in the circuit illustrated by the diagram
Απάντηση
(C)
4 W
42
Which of the following is not a consequence of hydrogen bubbles covering the copper plate of a primary cell?
Απάντηση
(B)
Local action
43
Calculate the length of a constantan wire of cross- sectional area 4 π x 10-8m2 and resistivity 1.1 x 10-6 Ω m required to construct a standard resistor of resistance 21 Ω. [Take π = 22/7]
Απάντηση
(B)
2.40 m
44
In a domestic circuit, electrical appliances and lamps are arranged in parallel across the mains so as to enable the
Απάντηση
(D)
voltage across the appliances not to be affected when the lamps are switched on and off
45
Calculate the time in which 4.8 kJ of energy would be expended when an electric heater of resistance 1.8 x 103Ω is used on a 240 V mains supply. (Neglect heat losses to the surrounding).
Απάντηση
(A)
150.0s
46
Lenz’s law of electromagnetic induction states that
Απάντηση
(B)
the induced current in a conductor is in such a direction as to oppose the change producing it
47
Which of the following statements is not correct?
Απάντηση
(B)
Magnetic fields are scalar quantities.
48
Calculate the energy stored in 20μF capacitor if the potential difference between the plates is 40 V.
Απάντηση
(B)
1.6x102J
49
The diagrams above show lines of force in electric fields. In which of the diagrams would a positive test charge experience the least force as it moves from x to y?
Απάντηση
(A)
I only
50
What is the electric potential at a point distance r from a proton of charge q placed in a medium of permittivity εo?
Απάντηση
(D)
q/4πεor
51
lf the frequency of the a.c. circuit illustrated is 500Hz/ π what would be the reactance in the circuit?
Απάντηση
(C)
200.00 Ω
52
Which of the following statements is correct about cathode rays? They are fast moving
Απάντηση
(E)
electrons
53
Which of the following gives rise to the line spectra obtained from atoms?
Απάντηση
(C)
Change of an electron from a higher to a lower energy level in the atom
54
A stream of alpha particles is projected into an electric field between two plates X and Y as shown in the diagram above. Which of the following is correct? The particles are
Απάντηση
(C)
deflected towards plate Y
55
An element whose half-life is 3 years has N atoms. How many atoms would have decayed after 9 years
