Motion in one dimension

Motion in one dimension

it is the motion of a body along a staright line in a fixed direction.

example-freely falling body

Scalar and vector quantities

scalar- the physical quantities which have only magnitude

example-mass, time, distance,speed, density etc..

Vector-the physical quantities having both magnitude and direction. example- force,weight, displacement, velocity, acceleration etc...

Poll

is momentum a scalar or vector? Hint :- momentum is the amount of motion contained in a body. it is the product of mass and velocity. p=mv is its formula where p=momentum v=velocity m= mass

• scalar

• vector

• both scalar or vector

• neither scalar or vector

when both car and bike moves at same speed, which has more momentum?

ans:- car as mass is more.

concept :-

momentum= mass X velocity

so we can say momentum is directly proportional to mass and velocity. si unit- kg m /s

Representing a vector

 $Force-\overrightarrow{F_1}$  

A man started from A moved to B then C then back to A. Find distance and displacement

• distance= 3 + 5 + 3+ 5 = 16m

• Dispalcement = 0

Find the displacement as the body moved from a to b then to c

•  $Displacement=\sqrt{3^2+4^2}=5m$  

• Dont forget to write direction so dispalcement = 5m north east

Find the distance and displacement as the body moves from a to b along a circular path to diametrically opposite point

•  $Dis\tan ce=\pi r=\frac{22}{7}\times7=22m$  

• Displacement=7+7=14m

The SI unit of both is m/s

A car moves 100 m east in 10 seconds. find its speed and velocity?

speed= distance/time=100/10=10m/s

velocity=10m/s east (mention direction if possible)

A train takes 2 hours to reach from station A to B and 3 hours to return back to A. If separtion between stations is 200 km. find average speed and average velocity?

• Average speed=400/5=80km/h

• Average velocity=0

Check your progress

Attempt a short

!!!!!!!!!!! quiz !!!!!!!!!!!!!

Multiple Choice

The physical quantities having direction

• scalar

• vector

Multiple Choice

momentum is a

• scalar

• vector

Multiple Choice

current flows from positive terminal to negative terminal. it has a direction. so current is a

• scalar

• vector

Multiple Choice

if a body changes its position with respect to surroundings it is in

• rest

• motion

Multiple Choice

The distance travelled by a body in a given direction along a straight line is called

• distance

• speed

• one dimensional motion

• displacement

Multiple Choice

if a body moved 12 m east and then 5 m north displacement is

• 13 m north east

• 17m north

• 17m North east

• 13 m south west

Multiple Select

m/s is the unit of

• speed

• distance

• velocity

• displacement

Multiple Select

which of the following can be zero for a moving body

• distance

• displacement

• speed

• velocity

Multiple Choice

if the body moved 1 m east and the 1 m north then displacement=?

• 2 m north east

•  $\sqrt{2\ }\ \ metres$  

• 4 m north east

•  $\sqrt{2}\ \ m\ north-east$  

Multiple Select

Which is / are scalar quantities?

• velocity

• work

• density

• distance

Poll

How was today's class

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Poll

How was today's class

• Average

• good

• excellent