These are estimates of their average speeds
over some duration of time. These are not the fastest speeds.
observe their movement in real life. If you observe their speed in meters/sec at home or
on road or in some outing, then you can estimate the speed in kmph. You
can also estimate their speeds based on the relative speeds like a dog runs
faster than a cat.
Dogs - 50 kmph
- 50 kmph
Rats - 24 kmph
- 0.3 kmph Cows - 12 kmph
Bullocks - 12 kmph Goats - 25 kmph
Cheetah - 100 kmph or more
Lion - 50 kmph to 60 kmph - cannot run at high speed for a long duration
Tiger 60 kmph
Elephants - 30 kmph
deer - 50 kmph - can run fast for relatively long duration
Wild horse - 60 km Swan on water - 10 kmph
Wild duck swims - 10 km/hour Rabbit - 20 km to 25 km
Crow - 40 kmph Eagle - 100 kmph or more
Wild dogs - 60 kmph
Crocodile - 10 kmph on land, 20 kmph in water
Fish - 50 to 100 kmph depending on the type of fish
Frog - 18 t o 20 kmph
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.
stations or airports, they accelerate or decelerate. An
covers usually around 60 km in 3/4 hour non-stop
between two big stations.
= 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
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
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
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
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
So acceleration of an elevator is
= 20/100 = 0.2 m/s²
Speed = 0.2 * time