Question

Suppose that a car traveling to the west (the - x direction) begins to slow down as it approaches a traffic light. Which statement concerning its acceleration in the x direction is correct? (A) It's acceleration is negative but it's velocity is positive (B) It's acceleration is positive, but ti's velocity is negative. (C) Both its acceleration and its velocity are positive.

Answer 1

Answer:

(A) it's acceleration is negative but but it's velocity is positive

Explanation:

In the question it is given that begins to slow down so its speed is decreasing it is does not means that its speed is negative

For example let first the velocity of the car is 30 m/sec and when its velocity decreases it becomes 20 m/sec in 5 sec

So it is not negative at all

Now the acceleration is the rate of change of velocity

$a=\frac{dv}{dt}$

$a=\frac{v_2-v_1}{dt}=\frac{20-30}{5}=-2 m/sec^2$

So acceleration is negative here

So option (a) will be the correct option