Question

a plane left 30 minutes late than its scheduled time and in order to reach the destination 1500 km away in time , it had to increase it speed by 100 km/h from the usual speed . find its usual speed.

Answer 1

HEY MATE!!! ❤❤❤HERE'S UR ANSWER!!!❤❤❤




THE USUAL TIME TAKEN BY THE AEROPLANE =3hrs.



THE USUAL SPEED =500km/hr.





SOME KNOWLEDGE ABOUT SPEEED,DISTANCE AND TIME :



SPEED:Speed is the distance traveled per unit of time. It is how fast an object is moving. Speed is the scalar quantity that is the magnitude of the velocity vector. It doesn't have a direction. A higher speed means an object is moving faster.




DISTANCE:Distance is a scalar quantity that refers to "how much ground an object has covered" during its motion. Displacement is a vector quantity that refers to "how far out of place an object is"; it is the object's overall change in position.






TIME:Time in physics is defined by its measurement: time is what a clock reads. In classical, non-relativistic physics it is a scalar quantity and, like length, mass, and charge, is usually described as a fundamental quantity.





HOPE THIS HELPS YOU!!! ❤❤

Answer 2

Solution :-

Let the original speed of train be x km/hr
New speed = (x + 100) km/hr

We know that,
Time = Distance / Speed

Given : A plane left 30 minutes or 1/2 hours later than the scheduled time.

According to the question,

=> 1500/x - 1500/(x + 100) = 1/2
=> (1500x + 15000 - 1500x)/x(x + 100) = 1/2
=> 2(15000) = x(x + 100)
=> 30000 = x² + 100x
=> x² + 100x - 30000 = 0
=> x² + 600x - 500x - 30000 = 0
=> x(x + 600) - 500(x + 600) = 0
=> (x - 500) (x + 600) = 0
=> x = 500 or x = - 600

∴ x ≠ - 600 (Because speed can't be negative)


Hence,
Its usual speed = 500 km/hr