Question

give me some important notes on motion.
class 9th
CBSE
(physics)​

Answer 1

Motion

• Those quantity which describes only magnitude is called as Scalar Quantity.

• Those quantity which describes magnitude and direction both are called as Vector Quantity.

• The total distance covered by the body per unit total time taken by the body is called as it's Average Speed.

Average Speed= Total distance covered/Total time taken

• Average Velocity is defined as the total displacement covered by a body per unit total time taken by a body.

Average velocity= Total displacement/Total time

• Acceleration is defined as rate of change of velocity with respective time.

Acceleration =Change in velocity/Time

a=v-u/t

where v= Initial velocity of a body

u= Final velocity of a body

t= Time taken by a body

• The negative value of the acceleration is called as Retardation or negative acceleration.
• If the body covers equal displacement in equal interval of time, then such motion is called as Uniform motion. Example - Motion of moon around the earth
• If the body covers unequal displacement Inequal interval of time, then such motion is called as Non-uniform motion. Example- A ball thrown vertically upwards.

Answer 2

Answer:

Motion is life. Lack of motion is death. Movement is a vital nutrient to your body, just as much as food, water or oxygen. It feeds the brain, producing essential nutrient stimulation (called proprioception).

Explanation:

hope it helps u