The addition of any numbers of vector provide the magnitude as well as the direction of the resultant vector, hence the mentioned first option is not true.
The addition of vector required to connect the head of the one vector with the tail of the other vector and any vector can be moved in the plane parallet to the previous location, so, the mentioned second and third options are true.
Answer:
20 pig callers
Explanation:
Given that:
A pig caller produced intensity level of a sound = 107 dB
To find how many pig callers required to generate an intensity level of 120 dB;
we have:
120 dB - 107 dB = 13 dB
Taking the logarithm function;

where;
= initial intensity


I = 19.95
I ≅ 20 pig callers
Explanation:
Starting position at x = 16m
Ending position at x = -25m
Time of flight = 4s
Unknown:
Distance flown = ?
Displacement = ?
Speed = ?
Velocity = ?
Solution:
To find the distance flown, we should understand that the body is moving on the x - plane;
So distance = 16 + 25 = 41m
Displacement is 41m to the left or -x axis
Speed is the distance divided by the time taken;
Speed =
=
= 10.25m/s
Velocity is 10.25m/s along -x axis