NECO GCE PHYSICS OBJ AND THEORY - BMASTERZ

NECO GCE PHYSICS OBJ AND THEORY

Physics OBJ:
1-10: DEEBCDBCDC
11-20: DADBCBBCAA
21-30: EECACCBABC
31-40: BDBDDCBAAA
41-50: EBEACCBDED
51-60: CBCCDECCEA

1a) 



I)


 Regular maintenance is essential to keep machines and the work environment safe and reliable.


II)


 It helps to eliminate workplace hazards.


1aii)  


Electrolysis can be used for electroplating of metals.


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3a)


 couple is a system of forces with a resultant (a.k.a. net or sum) moment but no resultant force. 


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4a)


The statement: The linear expansivity of copper is 0.000017k^-1 means that, A unit length of copper will expand in length by a fraction 0.000017k^-1 of the original per Kelvin rise in temperature.


4b) 


In plane mirror, if the object is

upright, the image is also upright, of same

size and does not change in size by moving

the mirror towards or away from the face.

 *While* in concave mirror, if the object is

upright, the image is also upright but

magnified and increases in size by moving the

mirror away from the face.


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15a)


The degree to which a specified material conducts electricity, calculated as the ratio of the current density in the material to the electric field which causes the flow of current.

6a)wavelength of a is the spatial period of the wave I.e the distance over which the wave's shape repeats, and thus the inverse of the spatial frequency.

7a


Critical angle c is the incident angle in the sender medium when the angle of refraction in the less medium is 90%.




7b

Sound waves are longitudinal wave(they travel in the same direction as the vibration) 

While



Light wave are transverse waves (they travel at right angles to the vibration)