As we all know that there will be a list of important questions for every subject which will fetch marks. So below is a list of important questions in Physics that are included from all the chapters.

Q1. What is an electromagnet with their uses?

Ans: An electromagnet is defined as a type of magnet that produces the magnetic field as the electric current flow through it. This magnetic field disappears when the electric current is turned off. This is the main advantage of electromagnet over permanent magnet as the magnetic field can be controlled.

Following are the list of uses of an electromagnet:

  • Electromechanical solenoid
  • MRI machines
  • Particle accelerator
  • Mass spectrometers
  • Induction heating for cooking.

Q2. How will the layer of ozone in the earth’s atmosphere be helpful?

Ans: For all the life forms on the earth, ozone is the natural process. The UV radiations that are harmful to all living beings are trapped in the ozone layer. Therefore, any changes in the ozone layer will directly affect the living beings on the earth and so it is helpful and important for the earth.

Q3. What is radioactivity?

Ans: Radioactivity is also known as radioactive decay and is defined as the emission of alpha, beta or gamma particles from the unstable atomic nuclei.

  • Alpha decay: It is a type of radioactive decay in which the alpha particles are emitted which then transforms into a different atomic nucleus with mass number reduced by four.
  • Beta decay: It is a type of radioactive decay in which the beta particles are emitted. Beta decay of neutron transforms into a proton. It is a consequence of the weak force.
  • Gamma particles: It is a type of radioactive decay in which the unstable atomic nuclei dissipates excess energy spontaneously and is known as gamma emission. These consists of the shortest electromagnetic wavelengths.

Q4. Why the colour red is selected for danger signal signs?

Ans: Red colour is selected for danger signal signs because the wavelength of the red colour is more and it is least scattered.

Q5. What is the angle of dip?

Ans: The angle of dip is also known as magnetic inclination or magnetic dip and is defined as the angle made with the horizontal by the earth’s magnetic field lines.

Stay tuned with BYJU’S for more important questions chapter-wise and class-wise.