Time, speed and distance all these terms are dependent on each other but before we walk you through mathematical formulas and calculation let's understand how having knowledge of time speed and distance can be very useful for us to save and manage our time.
In practical life,when we have to reach somewhere we increase our normal speed or if we want to reach late we slow up our speed.Also if you are a bit more intelligent you can also calculate the distance you have covered if you know your constant speed and How much time you moved up.
Through the things we discussed above you must have got a lead that how time and speed are opposite to each other.i.e when Speed increases time decreases automatically.
Now let's how we calculate any one from time,speed and distance if the rest two are known.
What is speed :
Speed is defined as the distance covered in unit time
16 km/hours speed means 16 km distance is covered in 1 hour.
5 km/min speed means 5 km distance is covered in 1 minute.
2 km/s means 2 km distance is covered in 1 second.
Relation between Time speed and Distance
The mathematical relationship between Time(T) , Speed (S) and Distance (D) is given by the following formula:
To calculate Speed when Distance and time is given:
Speed = Distance/Time
S = D/T
To calculate Distance when Speed and time is known:
Distance = Speed×time
D =S×T
To calculate Time when Speed and distance is known:
Time = Distance/Speed
T = D/S
Time speed and distance Solved Examples
Q1 - John takes 20 minutes to reach his nearby shop that is 5 km apart. find his speed
Ans : Speed = Distance/Time
= 5 km/20 min
= 0.25km/min
John covers 0.25 km = 250 m in 1 minute.
Q 2 - A car is moving with a constant speed of 10 Km/hr for half an hour.Find the distance covered by it?
Ans: Distance = Speed ×Time
Time = 1/2 hour
Distance = 10 × 1/2
= 5 km
Q3 - Anna left her home with the speed of 5 km/hr to cover 25 km . How long will it take her to cover the distance?
Ans : Time = Distance/Speed
Speed= 5 km/hr
Distance= 25 km
Time = 25/5
= 5 hours
Q 4 - A 500 m long train passes a pillar in 5 seconds what is the speed of train?
Ans : Distance= Length of the Train=500m
Speed= Distance/Time
= 500/5
= 100m/s
Q 5 - A 50 meter banner is crossed in 40 s by a train coming with the speed of 80 m/s.find the length of the Train:
Ans : Let the length of the Train= x meter
Total Distance
= Banner Length+Train Length
= 50 + x
Speed of the Train = 80 m/s
Distance= Speed ×Time
50+x = 80×40
x = 320m
The length of the Train=320 meters
Difference between Speed and Velocity
Before we define velocity let's understand the Displacement.
Displacement : Displacement is the shortest Distance between starting point of a particle and its final position.
Velocity : Rate of change of displacement is called Velocity while Speed is defined as Rate of change of Distance.
In Physics Speed is A Scalar quantity which means it has magnitude only whereas Velocity is a Vector quantity that has magnitude as well as direction.
Note: Velocity May or May not be dependent on the total distance covered by a Particle for a particular time period but Speed always depends upon the total distance covered by a Particle for a particular time period.
FAQs Based on Time,Speed and Distance
Q 1 : How is the Ratio of speeds defined if the distance is constant ?
Ans : S1 / S2 = T2 / T1
Q 2 : How is the Ratio of times calculated if the two different distances are covered with same speed?
Ans : T1 / T2 = D1/ D2