Two cars are driving away from an intersection in perpendicular directions.The first car's velocity is 5 meters per second and the second car's velocity is 8 meters per second.At a certain instant, the first car is 15 meters from the intersection and the second car is 20 meters from the intersection.What is the rate of change of the distance between the cars at that instant (in meters per second)?Choose 1 answer:(A) 13(B) 25(C) 9.4(D) 89
Q. Two cars are driving away from an intersection in perpendicular directions.The first car's velocity is 5 meters per second and the second car's velocity is 8 meters per second.At a certain instant, the first car is 15 meters from the intersection and the second car is 20 meters from the intersection.What is the rate of change of the distance between the cars at that instant (in meters per second)?Choose 1 answer:(A) 13(B) 25(C) 9.4(D) 89
Formulating Triangle Hypotenuse: The distance between the two cars can be represented by the hypotenuse of a right triangle, where the legs are the distances of each car from the intersection.
Calculating Initial Distance: Let's call the distance of the first car from the intersection x1 (15 meters) and the second car x2 (20 meters). The hypotenuse (distance between the cars) is d.
Finding Square Root: Using Pythagoras' theorem, we calculate the initial distance between the cars: d2=x12+x22.
Determining Rates of Change: Plugging in the values: d2=152+202=225+400=625.
Applying Chain Rule: Taking the square root to find d: d=625=25 meters.
Solving for dtd: Now, we need to find the rate of change of d with respect to time (dtd). Since the cars are moving away from the intersection, we differentiate both x1 and x2 with respect to time.
Solving for dtd: Now, we need to find the rate of change of d with respect to time (dtd). Since the cars are moving away from the intersection, we differentiate both x1 and x2 with respect to time.The rate of change of x1 with respect to time (dtdx1) is the velocity of the first car, which is 5 m/s. Similarly, the rate of change of x2 with respect to time (dtdx2) is the velocity of the second car, which is d0 m/s.
Solving for dtd: Now, we need to find the rate of change of d with respect to time (dtdd). Since the cars are moving away from the intersection, we differentiate both x1 and x2 with respect to time.The rate of change of x1 with respect to time (dtdx1) is the velocity of the first car, which is 5 m/s. Similarly, the rate of change of x2 with respect to time (dtdx2) is the velocity of the second car, which is d0 m/s.Using the chain rule for differentiation, we get: d1.
Solving for dtd: Now, we need to find the rate of change of d with respect to time (dtd). Since the cars are moving away from the intersection, we differentiate both x1 and x2 with respect to time.The rate of change of x1 with respect to time (dtdx1) is the velocity of the first car, which is 5 m/s. Similarly, the rate of change of x2 with respect to time (dtdx2) is the velocity of the second car, which is d0 m/s.Using the chain rule for differentiation, we get: d1.Plugging in the values: d2.
Solving for dtd: Now, we need to find the rate of change of d with respect to time (dtd). Since the cars are moving away from the intersection, we differentiate both x1 and x2 with respect to time.The rate of change of x1 with respect to time (dtdx1) is the velocity of the first car, which is 5 m/s. Similarly, the rate of change of x2 with respect to time (dtdx2) is the velocity of the second car, which is d0 m/s.Using the chain rule for differentiation, we get: d1.Plugging in the values: d2.Simplify the equation: d3.
Solving for dtd: Now, we need to find the rate of change of d with respect to time (dtd). Since the cars are moving away from the intersection, we differentiate both x1 and x2 with respect to time.The rate of change of x1 with respect to time (dtdx1) is the velocity of the first car, which is 5 m/s. Similarly, the rate of change of x2 with respect to time (dtdx2) is the velocity of the second car, which is d0 m/s.Using the chain rule for differentiation, we get: d1.Plugging in the values: d2.Simplify the equation: d3.Divide both sides by d4 to solve for (dtd): d6 m/s.
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