Question

17. A train of length 200 m moving with speed of 90 km/hr crossing a bridge of length 300 m. Time taken by the train to cross the bridge is (1) 20 s (2) 10 s (3) 5 s (4) 25 s​

Answer 1

Answer:

20 s

Explanation:

Distance(d)= 300m + 200 m

             = 500 m

Speed(s)= 90km/hr

          = 90*1000/3600

          = 25 m/s

Time(t)=?

speed= Distance travelled / Time taken

Time taken= Distance travelled / speed

t=500/25

t= 20 s

I hope this answer helps you...

Please mark me as brainiest...

Answer 2

Answer:

A train of length 200 m moving with the speed of 90 km/hr crossing a bridge of length 300 m. Time taken by the train to cross the bridge is 20 second

The answer: option (1)

Explanation:

Total distance       =   length of the train + length of the bridge

                              =   300+200 = 500m

Speed of the train =  90 km/hr = $90\times \frac{5}{18} = 25 m/s$

Speed                    =   $\frac{Distance}{Time}$

                              =   $\frac{500}{25}$$= 20 s$