A projectile is shot upwards from the surface of the earth with an initial velocity of 108 meters per second.The position function is What is its velocity after 7 seconds?
A)The velocity after 7 seconds is 181.7 meters per second.
B)The velocity after 7 seconds is -142.3 meters per second.
C)The velocity after 7 seconds is 39.4 meters per second.
D)The velocity after 7 seconds is 73.7 meters per second.
E)The velocity after 7 seconds is -176.6 meters per second.

Question

A projectile is shot upwards from the surface of the earth with an initial velocity of 108 meters per second.The position function is  What is its velocity after 7 seconds?
A)The velocity after 7 seconds is 181.7 meters per second. 
B)The velocity after 7 seconds is -142.3 meters per second. 
C)The velocity after 7 seconds is 39.4 meters per second. 
D)The velocity after 7 seconds is 73.7 meters per second. 
E)The velocity after 7 seconds is -176.6 meters per second.

Quizplus · Accepted Answer

To find the velocity after 7 seconds, we need to find the derivative of the position function with respect to time, which gives us the velocity function.
Taking the derivative of the given position function, we get:
v(t) = -9.81t + 108
Substituting t = 7, we get:
v(7) = -9.81(7) + 108 = 39.4 m/s
Therefore, the velocity after 7 seconds is 39.4 meters per second.

A Projectile Is Shot Upwards from the Surface of the Earth