Nabteb Physics Question and Answer 2022

*PHYSICS OBJ*

1-10 DCBCACDACA
11-20 DBBDDDCCDA
21-30 CCCAABDACD
31-40 ABCBACBDBA
41-50 DCDACCCDDB

*COMPLETED*

*2022 NABTEB PHYSICS SOLUTIONS*

1ai. Pressure on a surface is defined as the amount of force exerted (thrust) on a surface per unit area.

II. diagram

1bi. Density is the ratio of mass & volume of a body while relative density is the ratio between density of an object (substance) and the density of some other reference object ( substance) at some given temperature.
Or
Unit of density is kg/m³ or g/cm³ while relative density is dimensionless

1bii.
Weight in air – weight in liquid/ weight in air – weight in water
==> 10 – 4 / 10 – 6 = 1.5

1ci. Capillarity is the tendency of a liquid in a capillary tube or absorbent material to rise or fall as a result of surface tension.

1cii.
– Rise of kerosene in the wick of a lantern
– sucking of ink by the blotting paper
– sucking of water by the towel

2ai.
– change in volume of a liquid with temperature
– change in resistance
– expansion of solid

2aii.
– it should be visible
– it should have uniform thermal expansion
– it should have a low freezing point
– it should have a high boiling point

2b.
– gas molecules are constantly moving
– gas molecules have negligible volume
– gas molecule have negligible intermolecular forces
– gas molecules undergo perfectly elastic collision

2ci. Charles law: This state that the volume of a fixed mass of gas is directly proportional to its absolute temperature when pressure remains constant

2cii. Boyle’s law: This state that the volume of a fixed mass of gas is inversely proportional to its pressure when temperature remains constant

2ciii. P1/T1 = P2/T2
T1= 30+273=303k
T2= 80+273=353k

990/303=P2/353
P2= 1,153.4mmhg

3ai. A musical note is a single tone of a specified pitch that is sustained for a given duration.

3aii.
String: guitar, violin
Pipe: folk pipe , tabor pipe
Percussion: drum, xylophone

3bi. Density & elasticity

3bii. This is because soundnhas a wavelength in the order of 1 meter and diffract very easily

3c. Diagram

5a. Diagram

5bi.
Cathode ray
– Cathode ray are a beam of electrons emerging from the cathode(negative terminal) within an electron tube. Electron are actual particles with mass & charge

– loading

X-ray
– x-ray are not charged particles but massless electromagnetic radiation

– loading

5bii.
– mammography
– joint changes & arthritis
– checking symptoms in the body
– diagnosing injuries

5c.
I= 3.0mA ~ 0.003A
V= 30kV ~ 30,000V
P= ?

P= IV
P= 0.003 X 30,000
P= 90watts.