If it takes 5.0 hrs to drain a container of 540.0cm3 of water, what is the flow rate of water from the container in kg-1? [Density of water = 1000kgm-3]
Trả lời
(D)
30.0kg-1 s
2
A boat travels due east at a speed 40ms-1s across a river flow due south at 30ms-1s. What is the resultant speed of the boat?
Trả lời
(C)
50.0ms-1
3
An object is projected with a velocity of 80ms-1 at an angle of 30o to the horizontal.The maximum height reached is
Trả lời
(B)
80m
4
A motor vehicle is brought to rest from a speed of 15ms-1 in 20 seconds. Calculate the retardation.
Trả lời
(A)
0.75ms-1
5
Which of the following is TRUE of a particle moving in a horizontal circle with constant angular velocity?
Trả lời
(C)
both energy and linear momentum are constant
6
An object of mass 50kg is released from a height of 2m.Find the kinetic energy just before it strikes the ground
Trả lời
(B)
1000J
7
A cone in an unstable equilibrium has its potential energy
Trả lời
(B)
increased
8
Calculate the magnitude of the force required to just move a 20kg object along a horizontal surface if the coefficient of friction is 0.2. [g = 10ms-2]
Trả lời
(B)
40.0N
9
Calculate the velocity ratio of a screw jack of pitch 0.3cm if the length of the tommy bar is 21cm
Trả lời
(D)
140\(\pi\)
10
A force of 15N stretches a spring to a total length of 30cm. An additional force of 10N stretches the spring 5cm further. Find the natural length of the spring
Trả lời
(B)
22.5cm
11
Which of these statements are TRUE of pressure in liquids? i. pressure acts equally in all direction. ii. pressure decreases with depth. iii. pressure at the same level of a liquid is the same. iv pressure is dependent on the cross-sectional area of the barometer tube
Trả lời
(A)
i, iii only
12
The mass of a specific gravity bottle is 15.2g when it is empty. it is 24.8g when filled with kerosene and 27.2g when filled with distilled water. Calculate the relative density of kerosene
Trả lời
(D)
0.80
13
If a solid X floats in liquids P of relative density 2.0 and in liquid Q of relative density 1.5, it can be inferred that the
Trả lời
(A)
weight of P displaced is greater than that of Q
14
The melting point of naphthalene is 78oC. What is this temperature in kelvin
Trả lời
(B)
351k
15
A Motor Tyre is inflated to pressure of 2.0 x 105Nm-2 when the temperature of air is 27oC. What will be the pressure in it at 87oC assuming that the volume of the Tyre does not change?
Trả lời
(B)
2.4 x 105Nm-2
16
When 100g of liquids L1 at 78°C was mixed with Xg of liquid L2 at 50°C, the final temperature was 66°C. Given that the specific heat capacity of L2is half that of L1, find x
Trả lời
(C)
150g
17
Heat is supplied to a test tube containing 100g of ice at its melting point. The ice melts completely in 1 min.What is the power rating of the source of heat? [Latent heat of fusion of ice = 336Jg-1]
Trả lời
(C)
560W
18
If a room is saturated with water vapour, the temperature of the room must be
Trả lời
(D)
below or at the dew point
19
Two similar kettles containing equal masses of boiling water are placed on a table. If the surface of one is highly polished and the surface of the other is covered with soot, Which of the following observations is correct
Trả lời
(C)
the kettle covered with soot cools down more quickly because it is a good radiator
20
The equation of transverse wave traveling along a string is given by Y = 0.3 sin(0.5x - 50t) where Y and X are in cm and t is in seconds.Find the maximum displacement of the particles from the equilibrium position
Trả lời
(D)
0.3cm
21
The sound from a source travelled to the bottom of the sea and the echo was heard 4s later. If the speed of sound in sea water is 1500ms-1 the depth of the sea is
Trả lời
(B)
3000m
22
The fundamental frequency of vibration of a sonometer wire may be halved by
Trả lời
(A)
doubling the length of the wire
23
A pipe of length 45cm is closed at the end. Calculate the fundamental frequency of the sound wave generated in the pipe if the velocity of sound in air is 360ms-1 [Neglect end correction]
Trả lời
(C)
200.0Hz
24
The note produced by a stretched string has a fundamental frequency of 400Hz. If the length of the string is doubled while the tension in the string is increased by a factor of 4, the frequency is
Trả lời
(B)
400Hz
25
To produce a parallel beam of light from a concave mirror, the distance at a which the lamp should be placed from the mirror is equal to
Trả lời
(A)
the focal length
26
Light of frequency 6.0 x 10\(^{14}\) Hz travelling in air is transmitted through glass or refractive index 1.5. Calculate the frequency of the light in the glass
Trả lời
(B)
6.0 x 1014Hz
27
An object is placed in front of a converging lens of a focal length 20cm. The image is virtual and has a magnification of 2. What is the distance of the object from the lens?
Trả lời
(B)
10cm
28
An object is placed directly below a glass block of thickness 3.0cm. Calculate the lateral displacement of the object if the refractive index of the glass is 1.5.
Trả lời
(A)
1.0cm
29
In a projection lantern of focal length f, the object distance u, is such that
Trả lời
(D)
f < u < 2f
30
If the Nigeria flag (green, white, green) is viewed in pure yellow light, which of the following set of colours would be observed on the flag?
Trả lời
(A)
Green, yellow, green
31
Which of the following has the lowest internal resistance when new?
Trả lời
(C)
Accumulator
32
When a biro pen rubbed on a dry silk cloth is moved very close to a piece of paper on a dry table, the pen is found to pick up the paper. This is because
Trả lời
(D)
both the pen and the cloth are charged
33
A capacitor 8\(\mu\)F is charged to a potential difference of 100V. The energy stored by the capacitor is
Trả lời
(D)
4.0 x 10-2J
34
Two capacitors R1 = 4\(\Omega\) and R2 = 5\(\Omega\) are connected in parallel across a potential difference. If P1 and P2 represent power dissipated in R 1 and R2 respectively, then the ratio P1 : P2 is
Trả lời
(B)
5 : 4
35
Which of the following are found in the receiver but not in the microphone of a telephone handset? i. Diaphragm. ii. soft iron pole pieces. iii. permanent magnet. iv.carbon blocks
Trả lời
(C)
ii and iii
36
If two parallel conductors carry currents flowing in the same direction, the conducts will
Trả lời
(A)
attract each other
37
A certain radioisotope of \(^{235}_{92}U\) emits four alpha particles and three beta particles. The mass number and the atomic number of the resulting elements respectively are
Trả lời
(A)
219 and 87
38
If light with photon energy 2eV is incident suitably on the surface of a metal with work function 3eV, then
Trả lời
(A)
no electron will be emitted
39
A spring of length 25cm is extended to 30cm by a load of 150N attached to one of its end, what is the energy stored in the spring?
Trả lời
(C)
3.75J
40
What is the reading of the vernier calipers shown above
