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__Uniform motion:__

- When a cyclist is covering 5km uniformly in every 1 hour

- a vehicle moving at constant speed on a straight road

__Non-uniform motion:__

- motion of a football player

- motion of a bike in a busy road

### This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.

Characteristics of uniform motion :

=============================

1. Same distance is covered (traveled) in equal intervals of time.

2. Distance Time graph shows a straight line. s = v t

3. Speed is constant. If the body is moving in a straight line, velocity is constant and

acceleration is zero. There is no net force acting on the body. Displacement always

increases and is in one direction.

4. If body is moving in a circle, the speed v is constant and acceleration = v²/R . Acceleration

points towards the center of circle. There is a centripetal force acting on the body.

Displacement increases and decreases in magnitude and changes in direction.

Centripetal force is constant.

Non-Uniform motion

1. Body moves unequal distances in same time intervals.

2. Distance Time graph is not a straight line. Speed is not a constant.

3. If the body is moving along a straight line, velocity is in the same direction and

acceleration is also in the same direction. Velocity & acceleration are not constant.

4. If the body is moving in a circle, then speed, velocity, acceleration are not constant.

5. Angular velocity is not constant. Centripetal force is not constant.

1. Earth rotates around itself with a uniform speed (almost)

So all of us are moving with a uniform speed (tangential) in circles, with

respect to a stationary observer outside earth. We have not taken into

account the revolution of earth around Sun here.

Our speed = radius of earth * angular velocity

= 6400 km * 2 π / 24 hours = 1675.5 kmph

2. Trains and air planes move with uniform speed in between halts. Near

stations or airports, they accelerate or decelerate. An express train

covers usually around 60 km in 3/4 hour non-stop between two big stations.

average speed = 60 / (3/4) = 80 kmph

5. Speed of Birds flying in air = distance traveled / time = 15 meters /sec = 54 kmph

7. Hard disk inside the computer. It rotates at uniform speed.

speed = 4,000 rpm - 10,000 rpm

9. Light wave moves at uniform speed of c = 3 * 10^8 m/sec

10. A fan (ceiling) rotates at a uniform speed, same with the blade in a

kitchen - mixie or mixer.

Tip of Fan wing : radius = 0.80 meter,

smallest speed = 5 rotations per sec

Angular speed = 5 * 2 p radians/sec = 10 p rad/sec

Uniform Linear speed of the tip (far end of a wing)

= 0.80 * 10 p m/sec = 25.13m/s = 90.5 kmph

11. Blood inside our body moves (circulates) at uniform speed

Pulse rate = 72 /min

Average distance from heart to a hand/leg = 2.5 m

Speed of blood flow = around 2.5m * 72 / min

= 180 m / min = 180 * 60/1000 = 10.8 kmph

1. In a cricket match the cricket ball is bowled and it travels the pitch at

an average speed in air and after bouncing from ground =

The ball takes 0.7 to 1 sec to reach batsman - observation.

speed = distance / time = 20 meters / 0.7 sec = 20/0.7 * 18/5 = 103 kmph for a pacer

and 20 m / 1 sec = 72 kmph for a spinner.

2. moon moves around the Earth with almost uniform speed

4. An object thrown in to air, like stone, moves at non-uniform speed.

4. Earth moves in an elliptical orbit non-uniform speed - its orbital speed

changes depending on its distance from the Sun. During summer Earth is

at 147 million km and (perihelon) during winter, it is at 152 million km.

Linear Speed at perihelon = 2 π R / T = 105,000 kmph

Linear Speed at apihelon = 2 π R / T = 109,000 kmph

5. Lift used to go up or down in a building - it moves at non-uniform speed -

accelerates and decelerates also. Lift reaches 4th floor (10meters) in

10 seconds with uniform acceleration starting from rest.

So acceleration of an elevator is = 20/100 = 0.2 m/s²

Speed = 0.2 * time m/sec

=============================

1. Same distance is covered (traveled) in equal intervals of time.

2. Distance Time graph shows a straight line. s = v t

3. Speed is constant. If the body is moving in a straight line, velocity is constant and

acceleration is zero. There is no net force acting on the body. Displacement always

increases and is in one direction.

4. If body is moving in a circle, the speed v is constant and acceleration = v²/R . Acceleration

points towards the center of circle. There is a centripetal force acting on the body.

Displacement increases and decreases in magnitude and changes in direction.

Centripetal force is constant.

Non-Uniform motion

1. Body moves unequal distances in same time intervals.

2. Distance Time graph is not a straight line. Speed is not a constant.

3. If the body is moving along a straight line, velocity is in the same direction and

acceleration is also in the same direction. Velocity & acceleration are not constant.

4. If the body is moving in a circle, then speed, velocity, acceleration are not constant.

5. Angular velocity is not constant. Centripetal force is not constant.

__Bodies moving in uniform speed__1. Earth rotates around itself with a uniform speed (almost)

So all of us are moving with a uniform speed (tangential) in circles, with

respect to a stationary observer outside earth. We have not taken into

account the revolution of earth around Sun here.

Our speed = radius of earth * angular velocity

= 6400 km * 2 π / 24 hours = 1675.5 kmph

2. Trains and air planes move with uniform speed in between halts. Near

stations or airports, they accelerate or decelerate. An express train

covers usually around 60 km in 3/4 hour non-stop between two big stations.

average speed = 60 / (3/4) = 80 kmph

5. Speed of Birds flying in air = distance traveled / time = 15 meters /sec = 54 kmph

7. Hard disk inside the computer. It rotates at uniform speed.

speed = 4,000 rpm - 10,000 rpm

9. Light wave moves at uniform speed of c = 3 * 10^8 m/sec

10. A fan (ceiling) rotates at a uniform speed, same with the blade in a

kitchen - mixie or mixer.

Tip of Fan wing : radius = 0.80 meter,

smallest speed = 5 rotations per sec

Angular speed = 5 * 2 p radians/sec = 10 p rad/sec

Uniform Linear speed of the tip (far end of a wing)

= 0.80 * 10 p m/sec = 25.13m/s = 90.5 kmph

11. Blood inside our body moves (circulates) at uniform speed

Pulse rate = 72 /min

Average distance from heart to a hand/leg = 2.5 m

Speed of blood flow = around 2.5m * 72 / min

= 180 m / min = 180 * 60/1000 = 10.8 kmph

__Bodies moving with non uniform speed :__1. In a cricket match the cricket ball is bowled and it travels the pitch at

an average speed in air and after bouncing from ground =

The ball takes 0.7 to 1 sec to reach batsman - observation.

speed = distance / time = 20 meters / 0.7 sec = 20/0.7 * 18/5 = 103 kmph for a pacer

and 20 m / 1 sec = 72 kmph for a spinner.

2. moon moves around the Earth with almost uniform speed

4. An object thrown in to air, like stone, moves at non-uniform speed.

4. Earth moves in an elliptical orbit non-uniform speed - its orbital speed

changes depending on its distance from the Sun. During summer Earth is

at 147 million km and (perihelon) during winter, it is at 152 million km.

Linear Speed at perihelon = 2 π R / T = 105,000 kmph

Linear Speed at apihelon = 2 π R / T = 109,000 kmph

5. Lift used to go up or down in a building - it moves at non-uniform speed -

accelerates and decelerates also. Lift reaches 4th floor (10meters) in

10 seconds with uniform acceleration starting from rest.

So acceleration of an elevator is = 20/100 = 0.2 m/s²

Speed = 0.2 * time m/sec