8. A turtle crawls along a straight line, which we will call the x-axis with the positive direction to the right. The equation f
1 answer:
(a) The turtle's initial velocity is 4 m/s, initial position of the turtle is 5 cm, and initial acceleration is -1.25 m/s².
(b) The time when the velocity of the turtle is zero is 3.2 s.
(c) The time taken for the turtle to return to its starting point is 6.4 s.
(d) The time taken for the turtle to travel 30 cm is 0.08 s.
<h3>Initial velocity of the turtle</h3>The initial velocity of the turtle is calculated as follows;
The initial acceleration of the turtle is calculated as follows;
x(t) = 5 + 4t - 0.625t²
x(0) = 5 cm
<h3>Time when the velocity becomes zero</h3>v(t) = 4 - 1.25t
0 = 4 - 1.25t
1.25t = 4
t = 4/1.25
t = 3.2 s
<h3>Time taken to return to starting point</h3>The total distance traveled is calculated as follows
v² = u² + 2ad
0 = (4)² + 2(-1.25)d
0 = 16 - 2.5d
2.5d = 16
d = 16/2.5
d = 6.4 m
Time to travel the given distance;
d = ut + ¹/₂at²
6.4 = (4)t + ¹/₂(-1.25)t²
6.4 = 4t - 0.625t²
0.625t² - 4t + 6.4 = 0
solve the quadratic equation using formula method;
t = 3.2 s
The time travel the distance two times, = 2 x 3.2 s = 6.4 s
<h3>Time taken for the turtle to travel 30 cm</h3>d = ut + ¹/₂at²
0.3 = (4)t + ¹/₂(-1.25)t²
0.3 = 4t - 0.625t²
0.625t² - 4t + 0.3 = 0
solve the quadratic equation using formula method;
t = 0.08 s
Learn more about velocity here: brainly.com/question/6504879
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The answer for the following answer is answered below.
- <u><em>Therefore the time period of the wave is 0.01 seconds.</em></u>
- <u><em>Therefore the option for the answer is "B".</em></u>
Explanation:
Frequency (f):
The number of waves that pass a fixed place in a given amount of time.
The SI unit of frequency is Hertz (Hz)
Time period (T):
The time taken for one complete cycle of vibration to pass a given point.
The SI unit of time period is seconds (s)
Given:
frequency (f) = 100 Hz
wavelength (λ) = 2.0 m
To calculate:
Time period (T)
We know;
According to the formula;
<u>f =</u><u></u>
Where,
f represents the frequency
T represents the time period
from the formula;
T =
T =
T = 0.01 seconds
<u><em>Therefore the time period of the wave is 0.01 seconds.</em></u>
6) b) 2.7 m/s
7) b) DCA
8) b) B
Explanation:
6)
In a displacement-time plot, the slope of the line is given by
where
is the change in the y-variable, so it is the displacement
is the change in the x-variable, so it is the time elapsed
So, the slope of the line in a displacement-time plot corresponds to the velocity:
Therefore, to find the velocity of the object, we have to estimate the slope of its curve.
To estimate the velocity of object B, we have to estimate the slope of the line tangent to curve B at 10 seconds.
By doing an estimate by eye, we see that the displacement of object B changes from -10 m to 0 m when time increases from about 8 s to 12 s, so the velocity is about:
So the closest option is b) 2.7 m/s.
7)
As we said in part A, the velocity of each object is given by the slope of each curve.
Therefore:
- The steeper the curve, the higher the velocity
- The less steep the curve, the lower the velocity
From the graph, we observe that, among A, C and D:
- Curve D has the largest slope (in absolute value), so object D has the largest magnitude of the velocity
- Curve C is less steep than curve C, so object C has the second largest magnitude of velocity
- Curve A is flat, so the slope is zero, so its velocity is zero
So, from greatest magnitude to lowest magnitude of velocity, we have:
b) DCA
8)
In the graph, the overall displacement of each object is given by the change in the y-variable, .
This means that the object with largest displacement is the object whose curve has the largest variation in y.
From the graph, we see that:
- Object b has the largest variation in y, from -15 m to 30 m, so
- Then, object D has the second largest displacement (in magnitude), from -15 m to 25 m,
Finally, object C has displacement
While object A has displacement zero. Therefore, the correct option is
b) B