Class 10 Physics Chapter 7 Question Answer

Important Class 10 Physics Chapter 7 Question Answer written by Honorable Mr. Qamar Jamal Suib. These computerized notes are very helpful in the preparation of Sound for students of the 10th class Physics and these are according to the paper patterns of all Punjab boards.

• Here are the detailed Class 10 Physics Chapter 7 Question Answer to help you prepare for your exams.
• Important Multiple Choice Questions ( MCQs ) with correct Answers of Chapter No. 16: Basic Electronics in Physics class 10th Urdu Medium.
• Important Short Questions with Correct Answers of Chapter No.16: Basic Electronics in Physics class 10th Urdu Medium.
• Deflection of electrons by electric field:
• We can set up electric field by applying a potential difference across two parallel metal plates placed horizontally separated by some distance. When an electron beam passes between the two plates, it can be seen that the electrons are deflected towards the positive plate. The reason for this is that electrons are attracted by the positive charges and are repelled by the negative charges due to force F=qE, where ‘q’ is the electron charge and E is the electric field due to plates. The degree of deflection of electrons from their original direction is proportional to the strength of the electric field applied.
• Deflection of electrons by magnetic field:
• Now we apply magnetic field at right angle to the beam of electrons by using a horseshoe magnet. We will notice that the spot of the electrons beam on the screen is getting deflected from its original direction. Now change the direction of the horseshoe magnet. We will see that spot on the fluorescent screen is getting deflected in the opposite direction.
• CATHODE RAY OSCILLOSCOPE (C.R.O):
• The cathode-ray oscilloscope is an instrument which is used to display the magnitudes of changing electric currents or potentials. The information is displayed on the screen of a “cathode-ray tube”. This screen appears as a circular or rectangular window usually with a centimetre graph superimposed on it. For example, the picture tube in our TV set and the display terminal of most computers are cathode-ray tubes.
• The cathode-ray oscilloscope (C.R.O) consists of the following components:
• The electron gun with control grid. The deflecting plates. A fluorescent screen.
• The Electron Gun: The electron gun consists of an electron source which is an electrically heated cathode that ejects electrons. Electron gun also has an electrode called grid G for controlling the flow of electrons in the beam. The grid is connected to a negative potential. The more negative this potential, the more electrons will be repelled from the grid and hence fewer electrons will reach the anode and the screen. The number of electrons reaching the screen determines the brightness of the screen. Hence, the negative potential of the grid can be used as a brightness control. The anode is connected to positive potential and hence is used to accelerate the electrons. The electrons are focused into a fine beam as they pass through the anode.
• The Deflecting Plates: After leaving the electron gun, the electron beam passes between a pair of horizontal plates. A potential difference applied between these plates deflects the beam in a vertical plane. This pair of plates provides the Y-axis or vertical movement of the spot on the screen. A pair of vertical plates provides the X-axis or horizontal movement of the spot on the screen.
• If you're looking for comprehensive 10th class physics chapter 7 question answer, you've come to the right place.
• The Fluorescent Screen: The screen of a cathode-ray tube consists of a thin layer of phosphor, which is a material that gives light as a result of bombardment by fast moving electrons. The CRO is used in many fields of science; displaying waveforms, measuring voltages, range-finding (as in radar), echo-sounding (to find the depth of seabeds). The CRO is also used to display heartbeats.
• ANALOGUE AND DIGITAL ELECTRONICS:
• The quantities whose values vary continuously or remain constant are known as analogue quantities. For example, the temperature of air varies in a continuous fashion during 24 hours of a day. If we plot a graph between time and temperature recorded at different times, we get a graph. This graph shows that temperature varies continuously with time. Therefore, we say that temperature is an analogue quantity. Similarly, time, pressure, distance, etc. are analogue quantities.