<h3><u>Answer;</u></h3>
The period of the wave is <u><em>4 seconds</em></u>
<h3>
<em><u>Explanation;</u></em></h3>
- <em><u>The period of a wave or periodic time is the time taken for one complete oscillation to occur.</u></em> In this case, one complete oscillation occurs when the wave moves from one crest to the next or a trough to the next. <em><u>This takes 4 seconds. Therefore the period is 4 seconds.</u></em>
- <em><u>Frequency on the other hand is the number of oscillations by a wave in one second. Thus, f = 1/T, that is frequency is the reciprocal of periodic time.</u></em>
Answer:
D)Not enough information
Explanation:
According to Pascal's principle, the pressure exerted on the two pistons is equal:
![p_A = p_B](https://tex.z-dn.net/?f=p_A%20%3D%20p_B)
Pressure is given by the ratio between force F and area A, so we can write
![\frac{F_A}{A_A}=\frac{F_B}{A_B}](https://tex.z-dn.net/?f=%5Cfrac%7BF_A%7D%7BA_A%7D%3D%5Cfrac%7BF_B%7D%7BA_B%7D)
The force exerted on each piston is just equal to the weight of the corresponding mass:
, where m is the mass and g is the gravitational acceleration. So the equation becomes
![\frac{m_A g}{A_A}=\frac{m_B g}{A_B}](https://tex.z-dn.net/?f=%5Cfrac%7Bm_A%20g%7D%7BA_A%7D%3D%5Cfrac%7Bm_B%20g%7D%7BA_B%7D)
Now we can rewrite the mass as the product of volume, V, times density, d:
![\frac{V_A d_A g}{A_A}=\frac{V_B d_B g}{A_B}](https://tex.z-dn.net/?f=%5Cfrac%7BV_A%20d_A%20g%7D%7BA_A%7D%3D%5Cfrac%7BV_B%20d_B%20g%7D%7BA_B%7D)
We also know that ![A_B = 2.0 m^2\\A_A = 1.0 m^2](https://tex.z-dn.net/?f=A_B%20%3D%202.0%20m%5E2%5C%5CA_A%20%3D%201.0%20m%5E2)
So we can further re-arrange the equation (and simplify g as well):
![\frac{V_A d_A}{1}=\frac{V_B d_B}{2}](https://tex.z-dn.net/?f=%5Cfrac%7BV_A%20d_A%7D%7B1%7D%3D%5Cfrac%7BV_B%20d_B%7D%7B2%7D)
![\frac{d_A}{d_B}=\frac{V_B}{2V_A}](https://tex.z-dn.net/?f=%5Cfrac%7Bd_A%7D%7Bd_B%7D%3D%5Cfrac%7BV_B%7D%7B2V_A%7D)
We are also told that block B has bigger volume than block A:
. However, this information is not enough to allow us to say if the fraction on the right is greater than 1 or smaller than 1: therefore, we cannot conclude anything about the densities of the two objects.
Answer:
3. Her angular speed increases because her angular momentum is the same but her moment of inertia decreases
Explanation:
II ωi the intial angular momentum of the skater. Her angular momentum changes to If ωf after pulling her arms in.
It must be noted that If is less than II, then it is because her arms now go round not far from the rotation axis which brings down the mementos of inertia.
Angular momentum does not change since torque is O.
Note: the mathematical representations are better written on the attached diagram.
A wave that transfers energy through vibrating In a medium
Answer:
d = ( -0.3 , 0.7 ) miles
Explanation:
The complete question is as follows:
" Take the north direction as the positive y direction and east as positive x. The origin is still where the student starts biking. Let d⃗ N be the displacement vector corresponding to the first leg of the student's trip. Express d⃗ N in component form.
Express your answer as two numbers separated by a comma (e.g., 1.0,2.0). By convention, the x component is written first.
A student bikes to school by traveling first dN = 0.800 miles north, then dW = 0.300 miles west, and finally dS = 0.100 miles south. "
Solution:
- The displacement vector d N is vector sum of all journeys. We will express +x as +i and +y as +j. Then displacement vector is given by:
d = dN + dW + dS
d = 0.8 j - 0.3 i - 0.1 j
d = - 0.3 i + 0.7 j
- The displacement vector d in component form is d = ( -0.3 , 0.7 ) miles