Jamb cbt / utme Likely Physics Questions with Answers Options now available

Two mirrors of the same length are arranges as show in the diagram. A ray of light NO strikes the system at O and emerges along PQ. The emergent ray has been deviated through

A

220o

B

200o

C

210o

D

180o

↪ Answer

22

A magnetic needle is suspended first at the earth’s north magnetic pole and then at a point on the magnetic equator. The respective angles between the needle and the horizontal are

A

0o and 0o

B

60o and 60o

C

90o and 90o

D

90o and 0o

↪ Answer

23

A hydrometer is an instrument for measuring the

A

a depth of water of water in a vessel

B

relative density of a liquid by the method of flotation

C

relative density of a liquid by finding the apparent loss in weight

D

relative humidity of the air

↪ Answer

24

Consider the three forces acting at O and in equilibrium as shown in the figure. Which of the following equations is/are CORRECT?

1. P1 sin θ1 = p1 cos θ2
2. P3 = P1 cos θ4  + P2cos2

III. P1sin⁡θ1=P2sin⁡θ2

A

I only

B

II only

C

III only

D

I, II and III only

↪ Answer

25

The refractive index of a liquid is 1.5. If the velocity of light in a vacuum is 3.0 x 108ms−1, the velocity of light in the liquid is

A

1.5 x 108ms−1

B

2.0 x 108ms−1

C

3.0 x 108ms−1

D

4.5 x 108ms−1

↪ Answer

26

A ship travelling towards a cliff receives the echo of its whistle receives the echo of its whistle after 3.5 seconds. If the speed of sound in air under the prevailing conditions is 250ms−1, how much closer is the ship to the cliff?

A

10m

B

1. 350m

C

175m

D

125m

↪ Answer

27

Which of the following statements about defects of vision is/are CORRECT?

1. For a long sighted person, close objects appear blurred
2. For a short sighted person, distant objects appear blurred

III. Short sight is corrected by using a pair of converging lenses

A

I only

B

II only

C

I and II only

D

II and III only

↪ Answer

28

Which of the following conditions are necessary and sufficient for total internal reflection to take place at the boundary between two optical media?

1. Light is passing from optical denser medium to optically less dense medium
2. Light is passing from optically less dense medium to optically denser medium to optically denser medium

III. Angle of incidence is greater

1. Angle of incidence is lesser

A

I and II only

B

II only III only

C

III and IV only

D

I and III only

↪ Answer

29

The linear expansivity of brass is 2 x 10−5  oC−1. If the volume of piece of brass is 2 x 10cm3 at 0oC. What will be its volume at 100oC?

A

10.06cm3

B

10.04 cm3

C

10.02 cm3

D

10.06 cm3

↪ Answer

30

The lower and upper fixed points marked on a Mercury-in-glass thermometer are 210mm above the lower fixed point in a room. What is the temperature of the room in degrees Celsius?

A

55.3oC

B

30.43oC

C

49.0oC

D

16.43oC

Heat is supplied uniformly at the rate of 100W to 1.0 x 10−2kg of a liquid for 20 seconds. If the temperature of the liquid rises by 5oC, then the specific heat capacity of the liquid is

A

2.0 x 102Jkg−1K−1

B

2.0 x 102Jkg−1

C

4.0 x 104Jkg−1K−1

D

4.0 x 104Jkg−1

↪ Answer

32

Two drivers G and H are at depths 20m and 40m, respectively below the water surface in a lake. The pressure on G is O1 while the pressure on H is P2, If the atmospheric pressure is equivalent to 10m2 of water, then the value of P2/P1 is

A

0.50

B

0.60

C

1.67

D

2.00

↪ Answer

33

The fiqure above represents a block-and-tackle pulley system on which an effort of W Newtons supports a load of 120.0N. If the efficiency of the machine is 40o, then the value of W is

A

28.0N

B

48.0N

C

288.0N

D

50.0N

↪ Answer

34

In an experiment in which molten naphtha-line is allowed to cool, the cooling curve i n the figure was obtained. The temperature 80oC is known as the

A

cooling temperature

B

boiling point

C

melting point

D

vaporization point

↪ Answer

35

In the figure, the value of R is

A

3Ω

B

6Ω

C

4Ω

D

5Ω

↪ Answer

36

Which of the following instruments consumes the highest current?

2

A

I

B

II

C

III

D

IV

↪ Answer

37

Which of the following pairs is NOT part of the electromagnetic spectrum?

1. Radio waves
2. Beta rays

III. Gamma rays

1. Alpha rays

A

I and II

B

III and IV

C

I and III

D

II and IV

↪ Answer

38

A substance has half of 3 min. After 6 min, the count rate was observed to be 400. What was its count rate at zero time?

A

1600

B

1200

C

200

D

2400

Natural radioactivity consists of emission___

A

α-particles and β-rays

B

α-particles and X-rays

C

γ-ray and X-rays

D

α-particles and β-rays and γ-rays

↪ Answer

12

If a source of solid is moving, a stationary listener will hear a sound of different frequency. This is called?

A

doppler effect

B

resonance

C

ultra sound

D

rarefaction

↪ Answer

13

Which of the following can be described as high tension transmission?

A

High resistance and low voltage

B

Low current and high voltage

C

High current and low voltage

D

High current and low resistance

↪ Answer

14

What is the cost of running five 50W lamps and four 100W lamps for 10 hours if electrical energy costs 2 Kobo per KWh?

A

N0.65

B

N0.39

C

N3.90

D

N0.13

↪ Answer

15

The mass of a proton is approximately equal to that of

A

an α-particle

B

a β-Particle

C

a neutron

D

an electron

↪ Answer

16

A transformer has 300 turns of wire in the primary coil and 30 turns in the secondary coil. If the input voltage is 100 volts, the input voltage is

A

5 volts

B

10 volts

C

15 volts

D

20 volts

↪ Answer

17

A solid weighs 4.8g in air, 2.8g in water and 3.2g in Kerosine. The ratio of desity of the solid to that of the kerosine is

A

2

B

32

C

23

D

3

↪ Answer

18

One of the following readings represents the measurement of the measurement of the length of a metal rod using vernier callipers. Taking the reading accuracy into consideration, the most likely one is

A

5.165cm

B

5. 5.165cm

C

5.0cm

D

5.160cm

↪ Answer

19

When a sound wave passes from air into water its

A

speed and frequency increases but its wavelength remains the same

B

speed and wavelength increases but its frequency remains the same

C

speed decreases

D

speed increases but its frequency and wavelength decreases

↪ Answer

20

A convex mirror is used as a driving mirror because

1. its image is erect
2. It has a large field of view

III. It has a long focal length

Identify the CORRECT statement(s)

A

I and III only

B

I and II only

C

II and IIII only

D

I, II and III only

A few grains of table salt were put in a cup of cold water, kept at constant temperature and left undistributed. Eventually all the water tested salty. This action is due to?

A

convection

B

osmosis

C

capillarity

D

diffusion

↪ Answer

2

The force required to make an object of mass m, travelling with velocity v, turn in a circle of radius r is

A

mv2r

B

mr2x

C

mrv

D

mvr2

↪ Answer

3

A machine gun with a mass of 5kg fires a 50g bullet at a speed of 100 ms−1. The recoil speed of the machine gun is

A

0.5 ms−1

B

1.5 ms−1

C

1 ms−1

D

2ms−1

↪ Answer

4

If in a simple pendulum experiment the length of the inextensible string is increased by a factor or four, its period is increased by a factor of?

A

4

B

π2

C

14

D

2

↪ Answer

5

In what range of temperature is the expansion of water anomalous?

A

+208oC to +212oC

B

-80oC + -76oC

C

0oC to +4oC

D

-4oC to +0oC

↪ Answer

6

Which of the following statements about radioactivity is true?

(i) Alpha particle is positively charged

(ii) Beta particle is negatively charged

(iii) Gamma ray is neutral

(iv) Beta particle has the  same mass as helium atom

(v) Gamma ray is charged.

A

i, ii, iii, iv only

B

i, ii, iii only

C

iv and v only

D

i, ii and v only

↪ Answer

7

In the study of Physics, temperature and heat are often confused with each other. Which of the following statements correctly defines these two elements?

A

Temperature is a measure of the average kinetic energy of the molecules of a substance

B

Heat is a measure of the total kinetic energy of the molecules in a system

C

Different materials require different amounts of heat to cause a given change in temperature

D

All of the above

↪ Answer

8

The effect of closing the key K in the circuit shown in the figure above would be to?

A

increase the current by 0.4A

B

reduce the current by 0.4A

C

increase the current by 0.6A

D

reduce the current by 0.6A

↪ Answer

9

Which of the following statements on the use of X-rays is incorrect? X-rays are used

A

In a hospital to obtain photographs of tissues and bones in the body

B

For the treatment of malignant growths like cancer cells

C

In detecting fingerprints

D

To reveal hidden flaws in metal castings and welded joints work of art

↪ Answer

10

Under which of the following conditions is work done?

A

A boy pushes unto a table

B

A stands on a table

C

A man supports a heavy food above his head with his hands

D

A woman holds a pot of water

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