Science Quiz for Grades 9-11

Which of the following statements about solar energy is correct? I. Solar energy is produced through the fusion process in the sun's core. II. Solar energy is the result of the conversion of helium gas into hydrogen in the sun's core. III. Solar energy is the outcome of the conversion of hydrogen gas into helium in the sun's core.

• I and II

• II and III

• Only I

• I and III

In the experiment shown in the figure, there is a bell, a magnet, and a light source inside a glass jar. The glass jar is connected to a vacuum tap. What happens when the vacuum tap is opened and the air is removed from the glass jar? I. Sound waves cannot travel through an empty space. II. The magnetic field created by the magnet cannot propagate in a vacuum. III. Light cannot travel through a vacuum.

• I and II

• II and III

• Only II

• Only I

Which of the following statements about nuclear fusion is correct?

• It occurs inside stars and inside planets.

• It occurs inside the Sun but not in other stars.

• It occurs in planets but not in stars.

• It involves the splitting of atomic nuclei into smaller nuclei.

Which of the following statements about ultrasound is correct? I. Ultrasound waves have frequencies higher than the upper audible limit of human hearing. II. Ultrasound waves have frequencies lower than the upper audible limit of human hearing. III. The speed of ultrasound waves in a vacuum is faster than the speed of the sounds we hear.

• I and II

• II and III

• Only I

• I and III

How does the sound appear to the observer when they run towards the stationary sound source with a speed of V and then move away from it? I. The observer will hear a low-frequency sound when approaching the motionless sound source, and a high-frequency sound when moving away. II. The observer will hear a high-frequency sound when approaching the motionless sound source, and a low-frequency sound when moving away. III. The observer will hear sound with longer wavelengths when approaching the stationary sound source, and sound with shorter wavelengths when moving away.

• I and III

• II and III

• Only II

• Only I

Which of the following statements about the radiation curve shown in the figure is correct? I. The radiation curve for different temperatures peaks at a wavelength that is inversely proportional to the temperature. II. As the temperature of the blackbody increases, the peak wavelength decreases. III. The intensity at all wavelengths increases as the temperature of the blackbody increases.

• I and II

• I and III

• I, II and III

• Only I

Which color of light will result in the maximum number of electrons being removed from the metal surface in the photoelectric experiment shown in the figure?

• Orange light

• Green light

• Blue light

• Yellow light

If the metal rod moves up and down at a faster rate, which of the following changes do we observe? I. The wavelength of the wave increases. II. The wavelength of the wave remains constant. III. The frequency of the wave increases. IV. The wavelength of the wave decreases.

• Only II

• II and III

• III and IV

• I and III

What is the term used for a powerful explosion that happens when a high-mass star completes its life cycle?

• Supernova

• Black hole

• Nebula

• Solar flare

Choose the correct colours for the shorter and longer wavelengths to fill in the blanks respectively.

• Blue-Red

• Red-Green

• Green-Yellow

• Yellow-Blue