Now answer the following questions. Beta particles are

Here are the answers to the questions from the image:

Question 1: Beta particles are

• Beta particles are high-energy, high-speed electrons or positrons emitted by certain types of radioactive nuclei.
• The correct option is D.

Question 2: A kilometre is larger than a millimetre by

• $1 \text{ kilometre} = 1000 \text{ metres} = 10^3 \text{ metres}$.
• $1 \text{ millimetre} = 0.001 \text{ metres} = 10^{-3} \text{ metres}$.
• The ratio is $\frac{10^3 \text{ m}}{10^{-3} \text{ m}} = 10^{3 - (-3)} = 10^6$.
• So, a kilometre is one million times larger than a millimetre.
• The correct option is B.

Question 3: Which of the following properties is not correct about photons? They

• Photons are particles of light. They have zero rest mass, always travel at the speed of light in a vacuum, and are always in motion. They do not have mass when at rest.
• The incorrect statement is that they have mass at rest.
• The correct option is D.

Question 4: Gravitational field intensity is

• I. Gravitational field intensity is a vector quantity, not a scalar, as it has both magnitude and direction.
• II. Due to the Earth's shape and rotation, gravitational acceleration (and thus intensity) is greatest at the poles.
• III. At the centre of the Earth, the net gravitational force is zero, so the gravitational field intensity is zero.
• Statements II and III are correct.
• The correct option is C.

Question 5: The temperature difference of 1K is equivalent to

• The Kelvin scale and the Celsius scale have the same size degree increments. Therefore, a temperature difference of $1 \text{ K}$ is equivalent to a temperature difference of $1^\circ \text{C}$.
• The correct option is A.

Question 8: All of the following constants except

• Planck's constant, the gravitational constant, and the speed of light in a vacuum are fundamental physical constants.
• The refractive index of glass is a material property that varies depending on the type of glass and the wavelength of light, so it is not a universal constant.
• The correct option is D.

Question 9: SONAR is a device used by to detect underwater objects and primary characteristic utilized.

• SONAR (Sound Navigation And Ranging) uses sound waves to detect objects underwater. It works by emitting sound waves and detecting their reflection off objects.
• The correct option is B.

Question 10: The lost volt of a cell is the potential difference across

• The "lost volt" refers to the voltage drop that occurs across the internal resistance of a cell when current flows through it. This voltage is "lost" internally and does not contribute to the external circuit.
• The correct option is C.