Answer:
vector of zero magnitude
Explanation:
The displacement is a vector magnitude, therefore, in addition to being a module, it has direction and sense.
In this case it moved 350 m and then returned the same 350 m, so the total displacement is zero.
If we draw the vector, one has a directional direction to the right and the other direction to the left, therefore when adding the two vectors gives a vector of zero magnitude
Answer:
(a) W=1.20×10⁴J
(b) U= -5.46×10⁴J
(c) Q= -4.26×10⁴J
Explanation:
Given that student does 1.20×10⁴J work
(a) W=1.20×10⁴J
Work done by student,so positive sign
During the process, his internal energy decreases by 5.46×10⁴J.
(b) U= -5.46×10⁴J.
As the Energy decreases therefore negative sign
For (c) Q
We know the formula

Answer:
0.786 Hz, 1.572 Hz, 2.358 Hz, 3.144 Hz
Explanation:
The fundamental frequency of a standing wave on a string is given by

where
L is the length of the string
T is the tension in the string
is the mass per unit length
For the string in the problem,
L = 30.0 m

T = 20.0 N
Substituting into the equation, we find the fundamental frequency:

The next frequencies (harmonics) are given by

with n being an integer number and f being the fundamental frequency.
So we get:


