A driver of a car travelling at 52kmh-1 applies the brakes and acceler...
Ans.
Initial speed of car A = 52 km/hr
Time at which the car A comes to a stop = 5 s
Initial speed of car B = 34 km/h
Time at which the car B comes to rest = 10 s
Speed versus time graph for two cars
:
In Fig. AB and CD are the speed-time graphs for the two cars whose initial speeds are 52 km/h and , respectively.
Distance covered by first car before coming to rest is equal to Are of traingle AOB.
Distance covered by the second car before coming to rest is,
Thus, the second car travels farther than the first car after the brakes are applied.
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A driver of a car travelling at 52kmh-1 applies the brakes and acceler...
Speed versus Time Graphs for the Two Cars
To compare the distances traveled by the two cars after the brakes were applied, we can plot the speed versus time graphs for both cars.
Car A:
Car A was initially traveling at a speed of 52 km/h and then applied the brakes, decelerating uniformly. The car comes to a complete stop in 5 seconds.
Let's plot the speed versus time graph for Car A:
- The initial speed of Car A is 52 km/h, which is equivalent to 14.44 m/s.
- The final speed of Car A is 0 m/s.
- The time taken for Car A to come to a stop is 5 seconds.
The graph for Car A would show a straight line starting at 14.44 m/s and decreasing uniformly to 0 m/s over a period of 5 seconds.
Car B:
Car B was initially traveling at a speed of 3 km/h and then applied the brakes slowly, decelerating uniformly. The car comes to a complete stop in 10 seconds.
Let's plot the speed versus time graph for Car B:
- The initial speed of Car B is 3 km/h, which is equivalent to 0.83 m/s.
- The final speed of Car B is 0 m/s.
- The time taken for Car B to come to a stop is 10 seconds.
The graph for Car B would show a straight line starting at 0.83 m/s and decreasing uniformly to 0 m/s over a period of 10 seconds.
Comparison and Explanation:
To determine which car traveled farther after the brakes were applied, we need to consider the area under the speed versus time graph, which represents the distance traveled.
Since both cars started at the same initial speed and came to a stop, the distance traveled is directly proportional to the time taken to stop. The longer it takes for a car to stop, the farther it will travel.
In this case, Car B took 10 seconds to come to a stop, while Car A took only 5 seconds. Therefore, Car B traveled a greater distance compared to Car A after the brakes were applied.
This can be visually observed on the graph as well. The graph for Car B has a longer horizontal line segment, indicating a longer time taken to stop and hence a greater distance traveled.
In conclusion, Car B traveled farther after the brakes were applied compared to Car A.
A driver of a car travelling at 52kmh-1 applies the brakes and acceler...
Nice job but I have question to you how to create the questions in photo and how to write here easily can you say something about this
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