Answer:
We have to take the two axes of coordinates, the X axis & the Y axis, and perform the equation of sum of forces on each of the X & y axes. In order to find the value of the respective forces. We can also perform summations of moments around a given point to find unknowns in deduced equations.
Explanation:
A free body diagram gives us a summary of the forces acting on a body. These forces can be equal to zero. Or equal to the product of its mass by acceleration.
Although in some cases special attention should be paid to the movement of the body by such forces, for example if the movement is at constant speed, the acceleration will be equal to zero. Therefore the sum of forces will be equal to zero when the speed is constant.
Finally we have to take the two axes of coordinates, the X axis & the Y axis, and perform the equation of sum of forces on each of the X & y axes. In order to find the value of the respective forces.
We can also perform summations of moments around a given point to find unknowns in deduced equations.
In the attached image we can see a beam which is subjected to loads, and performing a summation of moments around the pivoting point equal to zero (the beam is in balance) we can find the value of force F.
Your answer is C.
hope this helps!
Answer:
Apparent frequency increases for Bob and decreases for Jill.
Explanation:
Doppler effect refers to the apparent change in frequency when there is relative motion between source and the listener. When the source and listener move closer, the apparent frequency heard by the listener increases. And when the source and listener move away from each other, the apparent frequency heard by the listener decreases.
Thus, when the emergency vehicle approaches Bob, the apparent frequency of the siren increases. It moves away from Jill, the apparent frequency heard by the Jill decreases.