2. A car comes its From AtoB at B to t a speed of From speed average speed during the journey. moves back OF Date 50 km/he and 30 km/hr. Find it's average speed during the journey
When the car moves from A to B, it travels at an unknown speed, which we'll call "v1".
When the car moves from B to A, it travels at two different speeds - 50 km/hr and 30 km/hr. We can calculate the average speed for this portion of the journey using the formula for the average of two speeds:
average speed = (2 x speed1 x speed2) / (speed1 + speed2)
where speed1 and speed2 are the two speeds that the car travels at.
So the average speed of the car from B to A can be calculated as:
average speed = (2 x 50 km/hr x 30 km/hr) / (50 km/hr + 30 km/hr)
average speed = 3000 / 80
average speed = 37.5 km/hr
The total time taken for the journey is the sum of the time taken to travel from A to B and the time taken to travel from B to A.
Time taken to travel from A to B = d / v1
Time taken to travel from B to A = d / 37.5 km/hr
Total time taken = (d / v1) + (d / 37.5 km/hr)
The average speed of the car for the entire journey can be calculated by dividing the total distance traveled by the total time taken:
Therefore, the average speed of the car during the journey is given by the expression 2 / [(1 / v1) + (1 / 37.5 km/hr)], where "v1" is the speed of the car from A to B
Answers & Comments
Answer:
Step-by-step explanation:
Let's call the distance between A and B "d".
When the car moves from A to B, it travels at an unknown speed, which we'll call "v1".
When the car moves from B to A, it travels at two different speeds - 50 km/hr and 30 km/hr. We can calculate the average speed for this portion of the journey using the formula for the average of two speeds:
average speed = (2 x speed1 x speed2) / (speed1 + speed2)
where speed1 and speed2 are the two speeds that the car travels at.
So the average speed of the car from B to A can be calculated as:
average speed = (2 x 50 km/hr x 30 km/hr) / (50 km/hr + 30 km/hr)
average speed = 3000 / 80
average speed = 37.5 km/hr
The total time taken for the journey is the sum of the time taken to travel from A to B and the time taken to travel from B to A.
Time taken to travel from A to B = d / v1
Time taken to travel from B to A = d / 37.5 km/hr
Total time taken = (d / v1) + (d / 37.5 km/hr)
The average speed of the car for the entire journey can be calculated by dividing the total distance traveled by the total time taken:
Average speed = (2d) / [(d / v1) + (d / 37.5 km/hr)]
Simplifying this expression by taking the common factor of "d" in the denominator, we get:
Average speed = (2d / d) / [(1 / v1) + (1 / 37.5 km/hr)]
Average speed = 2 / [(1 / v1) + (1 / 37.5 km/hr)]
Therefore, the average speed of the car during the journey is given by the expression 2 / [(1 / v1) + (1 / 37.5 km/hr)], where "v1" is the speed of the car from A to B