Question 1 A working electric motor takes a current of 1.5A when the p.d. across it is 250V. If its efficiency is 80%, the power output is{UTME 2001} A. 469.0W B. 300.0W C. 4.8W D. 133.0W Solution Efficiency = (power output / power input)% power input = IV = 1.5*250 …

Read More »## How to solve questions on alternating current circuit for UTME

Question 1 The current output form of an a.c. source is given as I = 10 sin w t. The d.c. equivalent of the current is {UTME 2012} A. 5.0A B. 7.1A C. 10.0A D. 14.1A Solution I = I0 sin wt Comparing this with the equation in the question …

Read More »## Questions and answers on Magnetic field and E.M induction for UTME

Question 1 Induced emfs are best explained using{UTME 2013} A. Lenz’s law B. Ohm’s law C. Faraday’s law D. Coulomb’s law Solution Athough both Faraday and Lenz explained the induced emf Faraday’s law talk about the emf is induced as a result of the rate of change of magnetic flux …

Read More »## Notes on application Physics for Cambridge A level students

ELECTRONIC SENSOR SENSING UNIT : This produce input voltage to processor depending on change in physical properties e.g temperatue, light or pressure. Piezo electric Transducer It converts energy from one form to another e.g microphone Quartz, a crystal has its positive and negative ion joined at the centre When pressure …

Read More »## Solutions to Cambridge A level June 2015 and 2016 physics

Question 1 The average kinetic energy E of a gas molecule is given by the equation E = 3/2 kT where T is the absolute (kelvin) temperature. What are the SI base units of k ? A kg–1m–1s2K B kg–1m–2s2K C kg m s–2K–1 D kg m2s–2K–1 Solution The S.I …

Read More »## How to solve questions on linear expansivity

Linear expansivity is defined as the increase in length, of the unit length of the material for one degree temperature rise. In order to solve any question on linear expansity: (i) Write down the formula (ii) Write down the data given (iii) Understand what you are asked to find (iv) …

Read More »## Notes on quantization of energy

Max planck explained that energy from such bodies is emitted in separate or discrete packets of energy known as energy quanta or photo of amount hv where v is the frequency of radiation and he represents Planck’s constant, then energy by the equation E = nhf f = c/λ c …

Read More »## More solutions to some UTME past questions

Question 1 The energy of a photon having a wavelength of 10^-10m is{utme 2013} A. 1.7 x 10-12J B. 2.0 x 10-15J C. 1.7 x 10-13J D. 2.0 x 10-12J Solution E = hf = hc/λ h is the planck’s constant = 6.63 × 10–34 J s c is the …

Read More »## How to solve questions on simple machine and light waves for UTME

Question 1 A ray of light strikes a plane mirror at an angle of incidence of 35o. If the mirror is rotated through 10o, through what angle is the reflected ray rotated?{utme 2001} A. 45o B. 20o C. 70o D. 25o The reflected ray will rotate through the angle = …

Read More »## Notes on optics : light waves

Transmission of light Light can travel through a solid, liquid and gas or vacuum. Therefore, it does not need a maternal medium for its transmission. Types of object/substance 1 Opaque object: These are objects that do not allow light to pass through them, e. g wood, stone, table, wall, etc. …

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