Lesson Of Guruji

Very Important Questions For        Biology HSC Exam 2021                     1) State and Explain Mendel's law of Inheritance 2) "Test cross is a back cross but back cross is not necessarily a test cross" Explain 3) Write a note on Plieotropy 4) State and explain 'Law of Independant Assortment' with suitable example. 5) What is monohybrid cross?give reasons for Mendel's success. 6) Describe Watson and Crick model of DNA. 7) Explain mechanismof DNA replication with diagram. 8) Describe Hershey & Chase experiment to prove DNA is genetic materials. 9) Describe "Lac Operon" concept. 10) Explain transcription & translation. 11) What DNA replication is called semi conservation ? 12) Explain mechanismof DNA replication with diagram. 13) Describe the steps involved in recombinant DNA technologyWhat is bacteriophage? 14)Explain lytic cycle of bacteriop...

                          Q. Define terms: Fuel cell Q. Write the chemical equations involved in the following reactions:(i) Hoffmann-bromamide degradation reaction Q. The following data were obtained during the first order thermal decomposition of SO2Cl2 at a constant volume : SO2Cl2 (g) → SO2 (g) + Cl2 (g) Experiment       Time/s–          Total                                   1          pressure/atm         1                      0       ...

              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...

                 Important MCQ's 2020 1)The centripetal acceleration of the bob of a conical pendulum is a) rg/cos thita b) rg/L c) g/L d)rg/L cos thita 2)A satellite in a circular orbit around the earth has a total energy E (E < O) . It's potential energy is a) -2E b) -E c) E d) 2E 3) The moment of inertia of a solid sphere of mass M and diameter d about an arbitrary axis a distance D from the centre of the sphere is a)mD^2 [1+0.1 (d/D)^2] b)mD^2 [1+0.4 (d/D)^2] c)mD^2 [1+0.1 (D/d)^2] d)mD^2 [1+0.4 (D/d)^2] । 4) The maximum speed and maximum acceleration of a particle executing SHM are 2 m/s and pya /2 m/s^2. The time period of the motion is a) 8s b) 7s c) 4s d) 7/pya s 5) If a wire made of a brittle metal is stretched beyond the proportional limit but within the elastic limit, then a) the strain is plastic. b) the strain is elastic and is linearly proportional to the stress. ...

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...