Question

question 12 (1 point) saved
the slope of a position - time graph measures which of the following quantities?
(a) average acceleration
(b) instantaneous velocity
(c) average velocity
(d) distance
question 13 (1 point) saved
if you walk 450 m north and then 200 m south, what is your displacement?
(a) 250 m
(b) 250 m north
(c) 650 m
(d) 650 m north

Explanation:

Step1: Define displacement

Displacement is a vector quantity. It is the difference between the final and initial positions.
Let the north - direction be positive.
The first displacement \(d_1 = + 450\space m\) (north) and the second displacement \(d_2=-200\space m\) (south).

Step2: Calculate the net displacement

The net displacement \(D=d_1 + d_2\).
Substitute the values: \(D = 450+( - 200)\).

$$D=450 - 200=250\space m$$

(north)

Answer:

B. 250 m north