This graph shows the position of a particle as a function of time. What is its instantaneous velocity at t = 7s?
A) 3 m/s
B) -3 m/s
C) 12 m/s
D) -12 m/s
E) Need additional information.

Question

This graph shows the position of a particle as a function of time. What is its instantaneous velocity at t = 7s? 
A) 3 m/s 
B) -3 m/s 
C) 12 m/s 
D) -12 m/s 
E) Need additional information.

Quizplus · Accepted Answer

The instantaneous velocity at any given time can be found by taking the derivative of the position function with respect to time. In this case, the slope of the tangent line at t = 7s is negative, indicating that the particle is moving in the negative direction. The slope of the tangent line appears to be approximately -3, so the instantaneous velocity at t = 7s is -3 m/s. Therefore, the best choice is B.

This Graph Shows the Position of a Particle as a Function