two trains 120m and 80m in length are travelling in opposite directions with velocities 42kmh-1 and 30kmh-1 respectively ? how much time will they require to completely cross each other ?
Answers
Answer:
Explanation:
let the length of 1st train L1= 120m
length of 2nd train L2= 80m
speed of 1st train S1=42 km/hr
speed of 2nd train S2 = 30 km/hr
now formula is
speed= distance/ time
so,
S1 + S2 = (L1 + L2)/ time
(42 + 30) km/hr = (120+80) m/ time
72 km/hr = 200 m/ time
now convert the speed from km/hr to m/s by multipying 5/18
72*5/18 = 200/ time
20 m/s = 200 m/ time
time= 200/ 20
time = 10 seconds
so the train will cross each other in 10 seconds
Answer:
let the length of 1st train L1= 120m
length of 2nd train L2= 80m
speed of 1st train S1=42 km/hr
speed of 2nd train S2 = 30 km/hr
now formula is
speed= distance/ time
so,
S1 + S2 = (L1 + L2)/ time
(42 + 30) km/hr = (120+80) m/ time
72 km/hr = 200 m/ time
now convert the speed from km/hr to m/s by multipying 5/18
72*5/18 = 200/ time
20 m/s = 200 m/ time
time= 200/ 20
time = 10 seconds
so the train will cross each other in 10 seconds