Question 1Two cars X and Y travelling in opposite directions along the same highway at uniform velocities 110kmhr-1 and 90kmhr-1A.200kmh-1B.100kmh-1C.40kmh-1D.20kmh-1Objective Show full explanation
Question 2A simple harmonic oscillator has a period of 0.02s and amplitude of 0.25m. Calculate the speed on ms-1 at the centre of the oscillation.A.1.25πB.25.00πC.100.00πD.400.00πObjective Show full explanation
Question 3A moving body of mass 25.0 kg undergoes a uniform retardation of 20.0 ms-2. Calculate the magnitude of the retarding force. A.1.25NB.8.00NC.45.00ND.500.00NObjective Show full explanation
Question 4A thermometer records 680 mmHg at steam point and 440 mmHg at ice point. The temperature it records at 380 mmHg is A.-25°CB.-20°CC.20°CD.25°CObjective Show full explanation
Question 5The pressure P, volume V and absolute temperature T of a given mass of an ideal gas change simultaneously. Which of the following equations is correct about the gas?A.PV = constant/TB.P/T = constantC.P/V = constant/TD.1/T = constant/PVObjective Show full explanation
Question 6An electron moves with a speed of 2.0 × 108ms-1 in a straight line. Calculate the wavelength of the electron wave.[mass of an electron = 9.1 × 10-31kg][Planck's constant = 6.6 × 10-34]A.3.63 × 10-10mB.6.51 × 10-9mC.4.24 × 10-8mD.7.25 × 10-8mObjective Show full explanation
Question 7The energy associated with the emitted photon when a mercury atom changes from one state to another is 3.3 eV. Calculate the frequency of the photon. [e = 1.6 x 10-19 C; h = 6.6 x 10-34]A.8.0 x 1014 HzB.3.1 x 1052 HzC.1.3 x 10-15 HzD.3.2. x 10-53 HzObjective Show full explanation
Question 8The current in a reverse-biased junction is due to A.majority carriersB.holesC.minority carriersD.electronsObjective Show full explanation
Question 9The main purpose of the transformer in an a.c. radio set is to A.increase power to the radioB.convert energy from a.c. to d.c.C.step down the voltageD.step up the voltageObjective Show full explanation
Question 10A silicon material doped with an element of a certain group and an n-type semi-conductor is formed. The most likely group of the element is A.IB.IIC.IIID.VObjective Show full explanation