Explanation

• The signed area under a velocity-time graph gives displacement.
• Area above the time axis is positive, while area below it is negative.
• The total distance travelled is obtained by adding the absolute areas.

Last verified on 06-11-2026

Explanation

• The slope of a distance-time graph represents the speed of an object.
• Speed is calculated by dividing the change in distance by the change in time.
• A steeper slope indicates greater speed, while a horizontal line indicates that the object is at rest.

Last verified on 31-10-2026

Explanation

• Mars is known as the Red Planet due to its reddish appearance.
• Its surface contains iron oxide (rust) which gives it a red color.
• It is the 4th planet from the Sun in the solar system.
• Mars has two small moons: Phobos and Deimos.
• Mars is often called the “planet of future exploration”.

Last updated by NA on 05-11-2026

Explanation

• Wilhelm Conrad Rontgen discovered X-rays
• He was discovered on 8 November 1895.
• He got the Nobel Prize in Physics in 1901.

Additional questions

• The penetrating power of X-rays depends on their frequency

Last updated by NA on 05-11-2026

Explanation

• The average distance from the Earth to the Sun is approximately 150 million kilometers.
• It is also called 1 astronomical unit (or AU).

Last updated by NA on 04-11-2026