Answer:
A: All of the above
Explanation:
The instantaneous speed of an object is simply the current seed of the object at any given time. The SI unit is m/S and it is a vector quantity.
Therefore, according to the given options, they all have SI units that are consistent with distance and time which makes them all an example of instantaneous speed.
A compound Machine is 2 machines that work together in order to make a task easier.
Answer:
When the ball hits the ground, its velocity is -128 ft/s.
Explanation:
Hi there!
First, let's find the time it takes the ball to reach the ground (the value of t for which s(t) = 0):
s(t) = -16t² + 32t + 240
0 = -16t² + 32t + 240
Solving the quadratic equation with the quadratic formula:
t = 5.0 s (the other solution of the equation is rejected because it is negative).
Now, we have to find the velocity of the ball at t = 5.0 s.
The velocity of the ball is the change of height over time (the derivative of s(t)):
v = ds/dt = s'(t) = -32t + 32
at t = 5.0 s:
s'(5.0) = -32(5.0) + 32 = -128 ft/s
When the ball hits the ground, its velocity is -128 ft/s.
