Question

In which situation is the acceleration of the car negative?

A.)The velocity of a car was 75 km/h
B.)The velocity of a car reduced from 50 km/h over one minute
C.)The velocity of a car increased from 40 km/h to 75km/h over 15 minutes
D.)The velocity of a car increased from 40 km/sh at 2:00pm and at 4:00pm the velocity of the car was 85 km/h

Answer 1

Answer: B

Step-by-step explanation:

Progress Learning

Answer 2

Answer is: B.)The velocity of a car reduced from 50 km/h over one minute.

Ending velocity is defined as the velocity attained by a body after completing distance at certain time interval:

v(ending velocity) = v(initial velocity) + a·t.

a is acceleration attained by the body (in this examle car).

t is time (in this example one minute).

Because velocity is reduced, acceleration has negative sign.

An car average acceleration over a period of time is its change in velocity.