Question

At which point or points is the object speeding up? Select all that apply.

a) When velocity is positive and acceleration is positive
b) When velocity is positive and acceleration is negative
c) When velocity is negative and acceleration is positive
d) When velocity is negative and acceleration is negative

Answer 1

An object speeds up when velocity and acceleration vectors are in the same direction, which happens in options (a) and (d) when both vectors are positive or negative, respectively. Option b and c

Step-by-step explanation:

An object is speeding up when the direction of its velocity and acceleration vectors are the same. Referring to the original question, an object speeds up when both velocity and acceleration are positive (a), and when both are negative (d). This is because acceleration is in the direction of the change in velocity, and when it is in the same direction as motion, the speed of the object increases.

For example, if a car is moving to the right (positive velocity) and is pushed further right (positive acceleration), it will speed up. Conversely, if the car is moving to the left (negative velocity) and is pushed further left (negative acceleration), it will also speed up.

Therefore, options (b) and (c) describe situations where the object is slowing down since the velocity and acceleration vectors are in opposite directions. Option b and c