Time/Distance II

Q1:  

A train running at a speed of 72km/h croses a tree in 9s.What is the length of the train?

Ans: Speed of the train=72km/h

                                       =72x5/18

                                       =20m/s

          Length of the train=20x9=180m

Q2:  

A train running at a speed of 54km/h croses a tree in 18s.What is the length of the train?

Ans: Speed of the train=54km/h

                                       =54x5/18

                                       =15m/s

          Length of the train=15x18=270m

Q3:  

A train running at a speed of 108km/h croses a tree in 6s.What is the length of the train?

Ans: Speed of the train=108km/h

                                       =108x5/18

                                       =30m/s

          Length of the train=30x6=180m

Q4:  

A train of length 600m is passing a electric post near the track in 6s.What is the speed of the train?

Ans: Speed of the train=600/6

                                       =100m/s

                                       =100x18/5

                                       =360km/h

 

Q5:  

A train of length 400m is passing a tree near the track in 20s.What is the speed of the train?

Ans: Speed of the train=400/20

                                       =20m/s

                                       =20x18/5

                                       =72km/h

Q6:  

A train of length 300m is passing a electric post near the track in 9s.What is the speed of the train?

Ans: Speed of the train=300/90

                                       =10/3m/s

                                       =10x18/3x5

                                       =12km/h

Q7:  

How long does a train 110 m long running at the speed of 72 km/h take to cross a bridge of 130 m length?

Ans: Total distance traveled by the train for crossing the bridge=110+130 = 240 m

         Speed of the train=72 km/h

                                      =72 x 5/18 m/s

                                      =20 m/s

         Time taken by the train to cross the bridge        = 240/20

                                                                               = 12 s 

Q8:  

How long does a train 200 m long running at the speed of 36 km/h take to cross a bridge of 80 m length?

Ans: Total distance traveled by the train for crossing the bridge=200+80 = 280 m

         Speed of the train=36 km/h

                                      =36 x 5/18 m/s

                                      =10 m/s

         Time taken by the train to cross the bridge=280/10

                                                                       =28 s 

Q9:  

How long does a train 140 m long running at the speed of 90 km/h take to cross a platform of 110 m length?

Ans: Total distance traveled by the train for crossing the bridge=140+110 = 250 m

         Speed of the train=90 km/h

                                      =90 x 5/18 m/s

                                      =25 m/s

         Time taken by the train to cross the bridge=250/25

                                                                       =10 s