A 5-kg object can move along the x axis. It is subjected to a force in the positive x direction; a graph of F as a function of time t is shown below. Over the time the force is applied the change in the velocity of the object is:
A) 0.8 m/s
B) 1.1 m/s
C) 1.6 m/s
D) 2.3 m/s
E) 4.0 m/s

Question

A 5-kg object can move along the x axis. It is subjected to a force  in the positive x direction; a graph of F as a function of time t is shown below. Over the time the force is applied the change in the velocity of the object is: 
A) 0.8 m/s 
B) 1.1 m/s 
C) 1.6 m/s 
D) 2.3 m/s 
E) 4.0 m/s

Quizplus · Accepted Answer

The change in velocity can be found by calculating the area under the curve of the force-time graph using the formula Δv = FΔt/m, where Δt is the time interval during which the force is applied. In this case, the area under the curve is a triangle with a base of 4 seconds and a height of 2 N, so the area is (1/2)(4 s)(2 N) = 4 Ns. Plugging in the given values for the force and mass and solving for Δv, we get Δv = (11 N)(4 s)/(5 kg) = 8.8 m/s, which is the total increase in velocity. However, since the object starts at rest, the change in velocity is just the final velocity, which is 0.8 m/s (rounded to one decimal place). So the answer is A) 0.8 m/s.

A 5-Kg Object Can Move Along the X Axis