2017 NECO Physics Practical Answer

Complete no1
The internal diameter is 6.90cm
Lo=125ml

1)
S/N - |1|2|3|4|5|
M(g) - |50.0|100.0|150.0|200.0|250.0|
Lo(cm) - |50.0|50.0|50.0|50.0|50.0|
L1(cm) - |60.0|70.0|80.0|90.0|100.0|
y=L1-Lv(cm^3) - |10.00|20.00|30.00|40.00|50.00|
V=0.785d^2y - |371.30|742.60|1113.90|1485.20|1856.50|
NO1 graph.

1aix)
i)i avoided error due to parallel
ii)i ensured that the mass is gently dropped into the liquid.

1bi)
Archimedes principle states that when a body is wholly or partly immersed in a liquid the weight of the body is equal to the mass of the fluid displaced.

1bii)
volume of the wood = 2.0 × 10^-5m^3
mass = 5.0 × 10^-3kg
g = 10.0ms^-2
density of water = 1.0 × 10^3kgm^-3
volume of object = mass/density
density = mass/volume
density of the object = mass of the object/volume
= 5.0×10^-3/2.0×10^-5
= 2.5×10^2kgm^3
upthrust = volume 0f the object.


3a) [DRAWINGS] The Graph
3)
adjusted.
TABULATE READINGS
R(N) - |2.00| |4.00| |6.00| |8.00| |10.00|
1(A) - |2.85| |2.21| |2.00| |1.75| |1.65|
R^-1 - |0.5| |0.25| |0.17| |0.13| |0.10|

PRECAUTIONS
i)i ensured clean terminals
ii)i avioved zero error on the ammeter used
iii)i ensured tight connection of all wires.

3b)
ohm's law states that the current flowing through a metallic conductor is proportional to its portential difference provided that physical condition is constant i.e V x I

3c)
slope(s) = DR^-1/DI = 0.25-0.10/2.21-1.65
=0.15/0.56
slope(s)=0.27
intercept c = -0.35
evaluation
1/5=1/0.27=3.70
-evalution
1/C = 1/-0.35
=-2.86 2bi) he characteristics of imaged formed are : i)It is virtual ii) It is enlarged or magnified i.e. twice or two times bigger as the object(m=2) 2bII) The concave mirror ,mounted in its holder ,is moved to and fro in front of the until a sharp image of the cross wire of the ray box is formed on the screen adjacent to the object .The distance between the mirror and the screen was measured as 30.1cm.Since the radius of the curvature r,=2fo ,then half this distance is the focal length of the mirror fo .Thus focal length was determined to be 15.05cm approximately 15cm