The length of the bridge, which a train 130 metres long and travelling at 45 km/hr can cross in 30 seconds, is:200 m225 m245 m250 m

To solve this problem, we first need to convert the speed of the train from km/hr to m/s.

1 km/hr = 5/18 m/s

So, 45 km/hr = 45 * (5/18) = 25 m/s

The train crosses the bridge in 30 seconds. The distance covered in this time is the length of the train plus the length of the bridge.

So, Distance = Speed * Time

Therefore, 130m (length of the train) + Length of the bridge = 25 m/s * 30 s

Solving for the length of the bridge gives us:

Length of the bridge = (25 m/s * 30 s) - 130 m = 750 m - 130 m = 620 m

So, the length of the bridge is 620 meters. However, this option is not available in the choices provided. Please check the problem statement again.

To solve this problem, we first need to convert the speed of the train from km/hr to m/s.

1 km/hr = 5/18 m/s

So, 45 km/hr = 45 * (5/18) = 25 m/s

The train is 130 meters long and it takes 30 seconds to cross the bridge. So, in 30 seconds, the train travels a distance equal to its own length plus the length of the bridge.

We can use the formula: Speed = Distance/Time

Rearranging the formula to find the distance, we get: Distance = Speed * Time

So, the total distance the train travels in 30 seconds is: Distance = 25 m/s * 30 s = 750 meters

This distance is the length of the train plus the length of the bridge. So, the length of the bridge is: 750 meters - 130 meters = 620 meters

But none of the options match this result. There might be a mistake in the problem or the options provided.

To solve this problem, we first need to convert the speed of the train from km/hr to m/s.

1 km/hr = 5/18 m/s

So, 45 km/hr = 45 * (5/18) = 25 m/s

The train covers a certain distance in 30 seconds. The distance covered by the train is the length of the train plus the length of the bridge.

We can use the formula: Distance = Speed * Time

So, Distance = 25 m/s * 30 s = 750 m

This distance is the length of the train plus the length of the bridge.

So, the length of the bridge = Distance - length of the train = 750 m - 130 m = 620 m

Therefore, the length of the bridge is 620 m.

To solve this problem, we first need to convert the speed of the train from km/hr to m/s.

1 km/hr = 5/18 m/s

So, 45 km/hr = 45 * (5/18) = 25 m/s

The train travels at 25 m/s and it takes 30 seconds to cross the bridge.

So, the distance covered by the train (which is the length of the train plus the length of the bridge) in 30 seconds is:

Distance = Speed * Time = 25 m/s * 30 s = 750 m

This distance is the length of the train (130 m) plus the length of the bridge.

So, the length of the bridge is:

Length of the bridge = Distance - Length of the train = 750 m - 130 m = 620 m

So, the length of the bridge is 620 m.