Answer:
Swimming one time around the pool is 56.5 ft
Step-by-step explanation:
Swimming 18 ft from one side of her circular pool to the other, swimming straight through the center means the circular swimming pool has a diameter of d=18 ft.
The circumference of the circle is calculated using:
where d=18 is the diameter and π=3.14 as given.
We substitute the values to get:
We approximate to the nearest tenth to get:
Answer:
407 mi/h
Step-by-step explanation:
Given:
Speed of plane (s) = 470 mi/h
Height of plane above radar station (h) = 1 mi
Let the distance of plane from station be 'D' at any time 't' and let 'x' be the horizontal distance traveled in time 't' by the plane.
Consider a right angled triangle representing the above scenario.
We can see that, the height 'h' remains fixed as the plane is flying horizontally.
Speed of the plane is nothing but the rate of change of horizontal distance of plane. So,
Now, applying Pythagoras theorem to the triangle, we have:
Differentiating with respect to time 't', we get:
Now, when the plane is 2 miles away from radar station, then D = 2 mi
Also, the horizontal distance traveled can be calculated using the value of 'D' in equation (1). This gives,
Now, plug in all the given values and solve for . This gives,
Therefore, the distance from the plane to the station is increasing at a rate of 407 mi/h.
