WAEC 2018/19 Physics Obj And Theory Answers Out Online -WAEC 2018/19 Physics Obj And Theory Answers Out
Strain is a force (a part of one’s body or oneself) to make an unusually great effort.
i ) quantity of charge
ii) nature of element
iii ) Time
The boiling point of a liquid Is the point at which The vapour pressure is equal To atmospheric pressure
Satellite are used for monitoring weather conditions
i)Rockets are used for space travel
iii)launching satellites into space
7(a). LASER stands for Light Amplification by Stimulated Emission of Radiation.
(b). A laser is a device that emits a beam of coherent light through an optical amplification process.
10a) Diffraction refers to various phenomena that occur when a wave encounters an obstacle or a slit. It is defined as the bending of light around the corners of an obstacle or aperture into the region of geometrical shadow of the obstacle.
the angle of incidence beyond which rays of light passing through a denser medium to the surface of a less dense medium are no longer refracted but totally reflected.
binding energy is the minimum energy that would be required to disassemble the nucleus of an atom into its component parts. These component parts are neutrons and protons, which are collectively called nucleons.
(12b) They have short wire length and high frequency.
-They are highly penetrating
-They travel in straight line
-They don’t require material medium for their propagation
-It is used in production of electricity.
-It is used to study and detect charges in genetic engineering.
-It is used in agriculture.
-It is used in treatment of cancer.
E = hf-hfo
but f = v/landa
E= v/landa.h – wo
Where wo = hfo = work function
landa = wavelength
hf = hfo – E
f = hfo – E/h
f = wo – E/h
Recall; that v = f landa
Therefore f = v/landa = 3×10^8/4.5×10-7
=3/4.5 × 10^8+7
f = 6.6×10^14Hz
E = hf
=6.6×10^-34 × 6.6×10^14Hz
Energy of the photoelectron E = hf – vo
=Energy of incident electron – work function
=4.356×10^-19J – 3.0×10^-19J