Question

6.
Two trains 120 m and 80 m in length are running in
opposite directions with velocities 42 km hi' and 30 km
hl. In what time they will completely cross each other?

Answer 1

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)/sec

(42 + 30) km/hr = (120+80) m/sec

72 km/hr = 200 m/ sec

now convert the speed from km/hr to m/s by multipying 5/18

72*5/18 = 200/sec

20 m/s ( Ans)

⛔ NONEXISTENT ⛔