Motion :
MOTION: An Object is said to be in motion if its position changes w.r.t its immediate surroundings and time. REST: An Object is said to be at Rest if its position does not changes w.r.t its immediate surroundings and time.
MOTION AND REST ARE RELATIVE TERMS: An Object can be at rest and in motion w.r.t different surroundings at same time FOR EXAMPLE: Two Persons Sitting next to each other in a moving train are at rest with respect to each other . However both are in motion w.r.t a person standing outside the platform.
MOTION ALONG A STRAIGHT LINE: (1). Motion of a Train on Straight Track (2) An Apple Falling From a Tree (3)Hailstones Falling To the Ground
SPEED : Speed is an indicator of Motion. Speed = Distance per unit Time Speed = distance / time
S.I Unit of speed is meter / second (m/s). AVERAGE SPEED : TOTAL DISTANCE COVERED / TOTAL TIME TAKEN
UNIFORM AND NON- UNIFORM MOTION :AN object is said to be in Uniform Motion if it covers equal distance in equal time . for example : A Car moving along a straight narrow road when it travels first 30 km in first one hour ,next 30km in second 1 hour and next 30 km in 1 hour again.
Non uniform motion : An Object is said to be in non uniform motion if it covers equal distance in unequal interval of time ,unequal distance in equal time or unequal distance in unequal interval of time. for example car is travelling on a straight narrow road with lots of traffic on it.
CHAPTER 6 MOTION PDF DOWNLOAD
You can also Check:
DAV Board Class 7 Science Solutions Of Chapter 1
DAV Board Class 7 Science Solutions Of Chapter 2
DAV Board Class 7 Science Solutions Of Chapter 3
DAV Board Class 7 Science Solutions Of Chapter 4
DAV Board Class 7 Science Solutions Of Chapter 5
MEASUREMENT OF TIME : Early Scientists developed many devices to measure time intervals that are much smaller than a day. Devices like Sundial ,Hour glass ,Water clock etc.
Simple Pendulum:
Types of Motion in Simple pendulum : Oscillatory motion
To and fro ,back and forth periodic motion is said to be an oscillatory motion
Time taken to complete one oscillation by a pendulum is Known as time period of that pendulum.
Graph : Straight line parallel to time axis
Uniform motion : A straight line inclined to time axis or for constant speed .