Question

a car travels 30km/h at a uniform speed of 40km/h and next 30km/h at a uniform speed of 20km/h . find the average speed. plz full ans .​

Answer 1

Answer:

26.7 km/ hr

Step-by-step explanation:

Here , distance , s1=30km , speed v1=40km/h

distance , s2=30km , speed , v2=20km/h

If t1 and t2 the respective values of the time taken by car , then

t1=s1v1=3040=0.75h and t2=s2v2=3020=1.5h

As average speed =total distance travelled / total time taken ,

v av=s1+s2t1+t2=30+300.75+1.5=602.25=26.7km/h

Answer 2

Answer:

26.67 km/h

Step-by-step explanation:

THE TOTAL TIME FOR THE JOURNEY IS GIVENAS :-

$= > t = \frac{ d_{1} }{ v_{1} } + \frac{ d_{2} }{ v_{2} }$

$= > \frac{30}{40} + \frac{30}{20}$

$= > 2.25 \: \: \: hour$

THE AVERAGE SPEED IS GIVEN AS,

$= > v_{avg} = \frac{ d_{1} + d_{2}} {t}$

$= > \frac{30 + 30}{2.25}$

=>26.67 km/h

THUS,

THE AVERAGE SPEED OF THE CAR IS 26.67 KM/H

HOPE IT HELPS YOU☺️

AKRITI..!!