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Showing posts with the label Physics HSC 2020

Important Numericals for Physics HSC Board Exam 2021

              IMP Numericals 2021 1) A pilot of mass 90 kg in fighter aircraft executes a vertical circle of radius 2.8 km at a constant speed of 300 m/s. Calculate the force exerted by seat on the pilot i) at the bottom of the loop ii) at the top of the loop [ g=10 m/s^2] 2) Calculate the escape speed of a body from the surface of a planet of a radius 3000 km if the acceleration due to gravity at the surface of the planet is 2.5 m/s^2 3) A cylindrical mass of 10 kg rolls without slipping on a horizontal surface. At the instant the centre of a mass has a speed of 5 m/s^2 deter i) the transitional kinetic energy ii) the rotational kinetic energy about the axis through the centre of mass iii) the total kinetic energy of the cylinder. 4) A particle executes SHM with amplitude 6 cm and period 3 s. Find the speed of the particle at a point where its acceleration is half the maximum acceleration. 5) When a tensile load is applied to 1.8 cm diamet...

IMP Questions and Answers for Physics HSC Board Exam Feb 2021

1) Describe the construction of photoelectric cell. Ans - Construction — Photocell consists of evacuated glass tube containing two electrodes emitter (K) and collector (A).The emitter is shaped in the form of a semi hollow cylinder. It is always kept at a negative potential.The collector is in the form of a matal rod and fixed at the axis of the semi-cylinderical emitter. The collector is always kept as a positive potential.The glass tube is fitted on non-metallic base and pins are provided at the base for external connection. Working — The emitter is connected to negative terminal and collector is connected to positive terminal of a battery.A radiation of frequency more than threshold frequency of material of emitter is made incident on the emitter. Photo-emissions take place. The photoelectrons are attracted towards the collector which is positive w.r.t the emitter. Thus, current flows in the circuit.If the intensity of incident radiation is increased, the photoelectric cur...