Final answer:
Using the physics concept of kinematics and applying the formula v = u + at, the car that starts from rest and reaches a speed of 40 m/s in 10 s with a constant acceleration of 4 m/s^2 will be moving at 60 m/s 5 seconds later.
Step-by-step explanation:
The question pertains to the subject of physics, specifically kinematics, which deals with the motion of objects without considering the causes of the motion.
A car starts from rest and reaches a speed of 40 m/s in 10 s. Using the formula for acceleration (a = Δv/Δt), where Δv is the change in velocity and Δt is the change in time, we find that the acceleration (a) is 4 m/s2 (since the car started from rest, the change in velocity is simply the final velocity). Now, if the acceleration remains the same, to find the velocity after an additional 5 s, we can use the formula v = u + at. Here, 'u' is the initial velocity, which is 40 m/s at the end of the first 10 s, 'a' is the acceleration, which is 4 m/s2, and 't' is the time, which is 5 s.
The velocity after 5 s can be calculated as:
v = u + at
v = 40 m/s + (4 m/s2 × 5 s)
v = 40 m/s + 20 m/s
v = 60 m/s
So the car will be moving at 60 m/s 5 s later.