A train moves at a speed 72km/hr. When it approaches the station the driver brakes the train stops in 30 minutes.
a) what is the value of deceleration?
b) what is the duration it takes to stop?
Are you sure you copied that question correctly? It should not take 30 minutes to stop a train.
Why are they asking you the duration of stopping if they already told you it is 30 minutes?
I have no idea that is why i asked :/
To find the value of deceleration, we can use the formula:
Deceleration (a) = Change in Velocity ÷ Time
The initial velocity of the train is 72 km/hr, and it comes to a stop, so the final velocity is 0 km/hr. The change in velocity is the difference between the initial and final velocity, which is 72 km/hr.
The time taken to stop the train is given as 30 minutes, or 0.5 hours.
a) Putting the values into the formula:
Deceleration = (Change in Velocity) ÷ Time
Deceleration = (0 - 72) km/hr ÷ 0.5 hr
Deceleration = -72 km/hr ÷ 0.5 hr
Deceleration = -144 km/hr²
Therefore, the value of deceleration is -144 km/hr². The negative sign indicates that the train is decelerating (slowing down).
b) To find the duration it takes to stop, we already know that it takes 30 minutes, or 0.5 hours, to bring the train to a stop. Hence, the duration it takes to stop is 0.5 hours.