JAMB - Physics (2019)

• 1

  The limiting frictional force between two surface depends on

  I. the gaseous reaction between the surfaces

  II. the nature of the surfaces in contact

  III. the relative velocity between the surfaces

   

  תְשׁוּבָה

  (C)

  II only
• 2

  If a body moves with a constant speed and at the same time undergoes an acceleration, its motion is said to be

  תְשׁוּבָה

  (B)

  circular
• 3

  When blue and green colours of light are mixed, the resultant colour is

  תְשׁוּבָה

  (A)

  cyan
• 4

  A metal rod has a length of 100cm at 200\(^oC\). At what temperature will its length be 99.4cm. If the linear expansivity of the material of the rod is 2 x 10\(^{-5}C^{-1}\)

  תְשׁוּבָה

  (D)

  -100\(^o\)C
• 5

  According to kinetic molecular model, in gases

  תְשׁוּבָה

  (A)

  The molecule are very fast apart & occupy all the space made available
• 6

  

  The value of T in the figure above is

  תְשׁוּבָה

  (D)

  40N
• 7

  A train has an initial velocity of 44m/s and an acceleration of -4m/s\(^2\). Calculate its velocity after 10 seconds

  תְשׁוּבָה

  (D)

  4m/s
• 8

  Lamps in domestic lightings are usually in

  תְשׁוּבָה

  (D)

  parallel
• 9

  During the transformation of matter from the solid to the liquid state, the heat supplied does not produce temperature increase because

  תְשׁוּבָה

  (A)

  all the heat is used to break the bonds holding the molecules of the solid together
• 10

  In a slide wire bridge, the balance is obtained at a point 25cm from one end of wire 1m long. The resistance to be tested is connected to that end and a standard resistance of 3.6\(\Omega\) is connected to the other end of the wire. Determine the value of the unknown resistance

  תְשׁוּבָה

  (D)

  1.2\(\Omega\)
• 11

  Electrons were discovered by

  תְשׁוּבָה

  (C)

  J.J. Thompson
• 12

  Which of the following is/are the limitations to the Rutherford's atomic models?

  I. It is applicable when energy is radiated as electrons are revolving

  II. It is applicable when energy is radiated in a continuous mode

  III. It is applicable to an atom with only one electron in the other shell

  תְשׁוּבָה

  (C)

  I & II only
• 13

  Which of the following equations is the correct definition of the reactance of an indicator L?

  תְשׁוּבָה

  (A)

  Reactance = (Amplitude of voltage) \(\div\) (Amplitude of current)
• 14

  Ripple in a power supply unit is caused by

  תְשׁוּבָה

  (A)

  using an alternating current source
• 15

  When the temperature of a liquid is increased, its surface tension?

  תְשׁוּבָה

  (B)

  decreases
• 16

  The distance between an object and its real image in a convex lens is 40cm. If the magnification of the image is 3, calculate the focal length of the lens

  תְשׁוּבָה

  (B)

  7.5 cm
• 17

  A ray of light passes through the centre of curvature of a concave mirror and strikes the mirror. At what angle is the ray reflected?

  תְשׁוּבָה

  (C)

  0\(^o\)
• 18

  The pin-hole camera produces a less sharply defined image when the

  תְשׁוּבָה

  (A)

  pin-hole is larger
• 19

  A straight wire 15cm long, carrying a current of 6.0A is in a uniform field of 0.40T. What is the force on the wire when it is at right angle to the field

  תְשׁוּבָה

  (C)

  0.36N
• 20

  The pitch of a screw jack is 0.45cm and the arm is 60cm long. If the efficiency of the Jack is 75/π %, calculate the mechanical advantage.

  תְשׁוּבָה

  (C)

  200
• 21

  When the downward current flows in a straight vertical conductor, the direction of its magnetic field at a point due north of the wire is?

  תְשׁוּבָה

  (D)

  West
• 22

  Aluminium is sometimes used as the leaf of an electroscope because it

  תְשׁוּבָה

  (D)

  can be converted into thin sheets
• 23

  

  The diagram above represents the stress-strain graph of a loaded wire. Which of these statements is correct?

  תְשׁוּבָה

  (B)

  J is the yield point
• 24

  A supply of 400V is connected across capacitors of 3μf and 6μf in series. Calculate the charge

  תְשׁוּבָה

  (A)

  8 x 10\(^{-4}\)C
• 25

  A vibrator causes water ripples to travel across the surface of a tank. The wave travels 50cm in 2s and the distance between successive crests is 5cm. Calculate the frequency of the vibrator

  תְשׁוּבָה

  (A)

  5Hz
• 26

  A thermocouple thermometer is connected to a millivoltmeter which can read up to 10mV. When one junction is in ice at 0°C and the other is steam at 100°C, the millivoltmeter reads 4mV. What is the maximum temperature which this arrangement can measure

  תְשׁוּבָה

  (C)

  250\(^o\)C
• 27

  An alternating current can induce voltage because it has

  תְשׁוּבָה

  (B)

  varying magnetic field
• 28

  The limiting frictional force between two surfaces depends on
  I. the cohesive force of the material
  II. the nature of the surfaces in contact
  III. the relative velocity between the surfaces

  תְשׁוּבָה

  (B)

  II only
• 29

  During the transformation of matter from the solid to the liquid state, the heat supplied does not produce a temperature increase because

  תְשׁוּבָה

  (D)

  all the heat is used to break the bonds holding the molecules of the solid together
• 30

  The statement 'Heat lost by the hot body equals that gained by the cold one' is assumed when determining specific that heat capacity by the method of mixtures. Which of the following validates the assumption?
  I. Lagging the Calorimeter
  II. Ensuring that only S.I units are used
  III. Weighing the calorimeter, the lid and the stirrer.

  תְשׁוּבָה

  (C)

  I & III only
• 31

  In the molecular explanation of conduction, heat is transferred by the

  תְשׁוּבָה

  (A)

  Free electrons
• 32

  The conductivity of gases at low pressure can be termed as
  I. hot cathode emission
  II. thermo ionic emission
  III. cold cathode emission
  IV. Field emission

  תְשׁוּבָה

  (C)

  III & IV
• 33

  Which of the following media allow the transmission of sound waves through them?
  I. air
  II. liquid
  III. solids

   

  תְשׁוּבָה

  (D)

  I, II & III
• 34

  The earth's gravitational field intensity at its surface is about
  (G = 6.7 × 10\(^{-11}\)Nm\(^2\)/kg\(^2\), mass of the earth is 6 × 10\(^{24}\)kg, radius of the earth is 6.4 × 10\(^6\)m, g on the earth = 9.8m/s\(^2\))

  תְשׁוּבָה

  (D)

  9.8N/kg
• 35

  The following are parts of the eye
  I. Retina
  II. Pupil
  III. Iris
  The correct equivalent in the camera in the same order are

  תְשׁוּבָה

  (D)

  Film, Aperture, Diaphragm
• 36

  According to kinetic molecular model, in gases

  תְשׁוּבָה

  (C)

  The molecule are very fast apart & occupy all the space made available
• 37

  A force of 6N acts horizontally on a stationary mass of 2kg for 4s. The kinetic energy gained by the mass is _________

  תְשׁוּבָה

  (C)

  144j
• 38

  The momentum of a car moving at a constant speed in a circular track

  תְשׁוּבָה

  (C)

  can be zero depending on its inertia in the track
• 39

  A metal rod has a length of 100cm at 200°C. At what temperature will its length be 99.4cm. If the linear expansivity of the material of the rod is 2 × 10\(^{-5}\)C\(^{-1}\)

  תְשׁוּבָה

  (D)

  \(-100^0C\)
• 40

  The lead-acid accumulator consists of

  תְשׁוּבָה

  (D)

  tetraoxosulphate (vi) acid as the electrolyte
• 41

  When water is boiling, it

  תְשׁוּבָה

  (D)

  changes to steam
• 42

  A mixture of blue and red pigment when illuminated by white light will appear

  תְשׁוּבָה

  (D)

  magenta
• 43

  A siren having a ring of 200 hole makes 132 rev/min. A jet of air is directed on the set of holes. Calculate the frequency and wavelength in air of the note produced (take v = 350m/s)

  תְשׁוּבָה

  (A)

  0.795m
• 44

  A man on a bench will exert the greatest pressure on the bench when he

  תְשׁוּבָה

  (D)

  stands on the toes of one foot
• 45

  Gases conduct electricity under

  תְשׁוּבָה

  (D)

  low pressure & high voltage
• 46

  Neutrons were discovered by

  תְשׁוּבָה

  (C)

  James Chadwick
• 47

  The mass of a nucleus is the

  תְשׁוּבָה

  (A)

  total number of its proton & neutrons
• 48

  Three resistors with resistance 200Ω, 500Ω and 1kΩ are connected in series. A 6v battery is connected to either end of the combination. Calculate the potential difference between the ends of 200Ω resistance.

  תְשׁוּבָה

  (A)

  0.71V
• 49

  An a.c of 1A at a frequency of 800 cycles per second flows through a coil, the inductance of which is 2.5mH and the resistance of which is 5Ω. What is the power absorbed in the Coil?

  תְשׁוּבָה

  (A)

  5W
• 50

  In semi-conductor, the carriers of current at room temperature are

  תְשׁוּבָה

  (B)

  electrons and holes
• 51

  Water and Kerosine are drawn respectively into the two limbs of a Hare's apparatus. The destiny of water is 1.0gcm\(^{-3}\) and the density of kerosine is 0.80gcm\(^{-3}\). If the height of the water column is 20.0cm, calculate the height of the kerosine column.

  תְשׁוּבָה

  (D)

  25.0cm
• 52

  When a girl moves towards a plane mirror at a speed of 4.0m/s, the distance between the girl & her image reduces at a speed of

  תְשׁוּבָה

  (C)

  8 m/s
• 53

  One newton × One meter equals?

  תְשׁוּבָה

  (B)

  One Joule
• 54

  A microscope is focused on a mark on a table, when the mark is covered by a plate of glass 2m thick, the microscope has to be raised 0.67cm for the mark to be once more in focus. Calculate the refractive index.

  תְשׁוּבָה

  (A)

  1.50
• 55

  Radio waves belongs to the class of waves whose velocity is about

  תְשׁוּבָה

  (C)

  3 × 10\(^{8}\) m/s
• 56

  A single force which produces the same effect as a set of forces acting together at a point is known as the

  תְשׁוּבָה

  (C)

  resultant
• 57

  

  Which of the following statement about the electromagnet shown above is correct?

  תְשׁוּבָה

  (B)

  when the current flows from A to B, the end A will be south pole
• 58

  Calculate the velocity ratio of a screw jack of pitch 0.2cm if the length of the tommy bar is 23cm

  תְשׁוּבָה

  (A)

  230\(\pi\)
• 59

  The Earth's magnetic equator passes through Jos in Nigeria. At Jos, the

  תְשׁוּבָה

  (C)

  angle of dip is zero
• 60

  A car moving at 20m/s with its horn blowing (f = 1200Hz) is chasing another car going at 15m/s. What is the apparent frequency of the horn as heard by the driver being chased?

  תְשׁוּבָה

  (A)

  1.22KHz
• 61

  Any line or section taken through an advancing wave in which all the particles are in the same phase is called the

  תְשׁוּבָה

  (D)

  wave front
• 62

  

  In which of the points labelled A, B, C, D and E on the conductor shown would electric charge tend to concentrate most

  תְשׁוּבָה

  (D)

  E
• 63

  The point at which the molecules of a loaded wire begin to slide across each other resulting in a rapid increase in extension is

  תְשׁוּבָה

  (A)

  yield point
• 64

  

  The resultant capacitance in the figure above is

  תְשׁוּבָה

  (B)

  0.8μf
• 65

  The lower fixed part of a faulty thermometer reads 2°C while the upper fixed point is 100°C.
  What is the true temperature when the thermometer reads 51°C?

  תְשׁוּבָה

  (B)

  50°C
• 66

  If a body moves with a constant speed and at the same time undergoes an acceleration, its motion is said to be

  תְשׁוּבָה

  (A)

  circular
• 67

  

  A coil X is moved quickly away from the end Y of a stationary metal bar and a current then flows in X as shown above.
  Then

   

  תְשׁוּבָה

  (B)

  Y is a north pole
• 68

  A boy pushes a 500kg box along a floor with a force of 2000N. If the velocity of the box is uniform, the co-efficient of friction between the box and the floor is

  תְשׁוּבָה

  (D)

  0.4
• 69

  The following are some units
  I. Ns
  II. Non
  III. Nm\(^{-2}\)
  IV. J°K\(^{-1}\)
  V. JKg\(^{-1}\)
  What are the units of latent heat?

  תְשׁוּבָה

  (D)

  V
• 70

  When two objects A and B are supplied with the same quantity of heat, the temperature change in A is obtained to be twice that of B. The mass of A is half that of B. The ratio of the specific heat capacity of A to B is

  תְשׁוּבָה

  (C)

  1 : 1
• 71

  The volume of 0.354g of helium at 273°C and 114cmhg of mercury pressure is 2667cm\(^3\). Calculate the volume

  תְשׁוּבָה

  (A)

  2000.25 cm\(^3\)
• 72

  Which of these is observed when air is pumped out of a discharge tube without lowering its pressure

  תְשׁוּבָה

  (C)

  conduction does not occur
• 73

  Which of the following characteristics of a wave is used in the measurement of the depth of the Sea?

  תְשׁוּבָה

  (D)

  reflection
• 74

  If the attraction of the sun is suddenly ceased, the earth would continue to move in a straight line making a tangent with the original orbit. This statement is derived from Newton's

  תְשׁוּבָה

  (A)

  First law of motion
• 75

  Heat may be transferred by conduction, convection and radiation. By which of these methods does heat travel through vacuum?

  תְשׁוּבָה

  (C)

  Radiation only
• 76

  The part of the human eye that does similar work as the diaphragm of a camera lens is the

  תְשׁוּבָה

  (C)

  Iris
• 77

  A projectile of mass 4kg is fired vertically and reaches a maximum height of 40m. Calculate the potential energy at the highest point
  (g = 10ms\(^{-2}\)

  תְשׁוּבָה

  (B)

  1600J
• 78

  The length of the seconds hand of laboratory clock is 0.1m. Calculate the speed at the top of the seconds hand

  תְשׁוּבָה

  (A)

  1.05 × 10\(^{-2}\)ms\(^{-1}\)
• 79

  Workdone on an object to bring it to a certain point in space is called

  תְשׁוּבָה

  (A)

  Gravitational potential energy
• 80

  A copper rod, 5m long, when heated through 10ºC, expands by 1mm. If a second copper rod, 2.5m long, is heated through 5ºC, by how much will it expand?

  תְשׁוּבָה

  (B)

  0.25mm
• 81

  A safety precaution designed to prolong the life of a lead acid accumulator is

  תְשׁוּבָה

  (C)

  Keeping the specific gravity of the electrolyte within specified range
• 82

  The mass of water vapour in a given volume of air is 0.05g at 20°C, while the mass of water vapour required to saturate it at the same temperature is 0.15g. Calculate the relative humidity of the air.

  תְשׁוּבָה

  (C)

  33.33%
• 83

  The angular dispersion of a prism depends on

  תְשׁוּבָה

  (A)

  The index of refraction only
• 84

  Which of the following statements are correct of the production and propagation of waves?
  I. vibration produces waves
  II. waves transmit energy along the medium
  III. the medium through which the wave travels does not travel with the wave
  IV. waves do not require any medium for transmission

  תְשׁוּבָה

  (D)

  I, II and III only
• 85

  A rectangular solid block has length 10cm, breadth 5cm and height 2cm. If it lies on a horizontal surface, and has density 100kg/m\(^3\), calculate the pressure it exerts on the surface.

  תְשׁוּבָה

  (A)

  20 N/m\(^2\)
• 86

  

  The diagram shows four positions of the bob of a simple pendulum. At which of these positions does the bob have maximum kinetic energy and minimum potential energy

  תְשׁוּבָה

  (C)

  None Of The Above
• 87

  An object is acted upon by a system of parallel forces causing the object to be in state equilibrium. Which of the following statement is not correct

  תְשׁוּבָה

  (C)

  all the parallel forces must not be equal in magnitude and direction
• 88

  Which of the following statements is/are correct for a freely falling body?
  I. the total is entirely kinetic
  II. the ratio of potential energy to kinetic energy is constant
  III. the sum of potential and kinetic energy is constant

  תְשׁוּבָה

  (C)

  III only
• 89

  Efficiency of conduction in liquids and gases compared to solids is

  תְשׁוּבָה

  (A)

  less efficient than solid
• 90

  A well 1km deep is filled with a liquid of density 950kg/m\(^3\) and g = 10m/s\(^2\), the pressure at the bottom of the well is

  תְשׁוּבָה

  (A)

  9.6 × 10\(^6\)N/m\(^2\)
• 91

  "Sum of all forces acting on a body is zero." This condition represents equilibrium'

  תְשׁוּבָה

  (A)

  First condition
• 92

  

  Which of the following bodies, each with centre of gravity G, lying on a horizontal table, is/are in unstable equilibrium?

  תְשׁוּבָה

  (B)

  III only
• 93

  The volume of a stone having an irregular shape can be determined using?

  תְשׁוּבָה

  (B)

  measuring cylinder
• 94

  In Sunlight, a blue flower looks blue because we see the flower by the light it

  תְשׁוּבָה

  (D)

  reflect
• 95

  A body moves in SHM between two point 20m on the straight line Joining the points. If the angular speed of the body is 5 rad/s. Calculate its speed when it is 6m from the center of the motion.

  תְשׁוּבָה

  (C)

  40 m/s
• 96

  

  The diagram shows a uniform meter rule AB which balances horizontally at the 90cm mark when a mass of 0.2kg is suspended from B. Calculate the mass of the meter rule.

  תְשׁוּבָה

  (A)

  0.05kg
• 97

  The equilibrium position of objects in any field corresponds to situation of

  תְשׁוּבָה

  (C)

  minimum potential energy
• 98

  The height at which the atmosphere ceases to exist is about 80km. If the atmospheric pressure on the ground level is 760mmHg, the pressure at a height of 20km above the ground level is
  (ρm = 13.6g/cm\(^3\) ρ = 0.00013g/cm\(^3\) )

  תְשׁוּבָה

  (B)

  570mmHg
• 99

  A cone is in unstable equilibrium, has its potential energy

  תְשׁוּבָה

  (B)

  increased
• 100

  A mass of 0.5kg is whirled in a vertical circle of radius 2m at a steady rate of 2 rev/s. Calculate the centripetal force

  תְשׁוּבָה

  (C)

  158N