Question

Sarah throws a ball directly upward at the edge of a cliff with a starting velocity of 3.0 m/s

It lands on the ground with a final speed of 6.0 m/s
How long is the ball in the air?
Round the answer to two significant digits

Answer 1

Sarah throws a ball directly upward at the edge of a cliff with a starting velocity of 3.0 m/s. It lands on the ground with a final speed of 6.0 m/s.

How long is the ball in the air?

Answer: 0.92

Answer 2

The correct answer is t = 0.92s

Step-by-step explanation:

Initial velocity v​0 = 3.0 m/s

Displacement Δy = ?

Acceleration a = -9.8m/s2

Final velocity v = -6.0m/s

Time t=? Target unknown

We can use the kinematic formula missing Δy to solve for the target unknown t:

V=v0+at

We can rearrange the equation to solve to t:

V-v0=at

t= v-v0/a

Substituting the known value into the kinematic formula gives:

t= (-6.0m/s)-(3.0m/s)

————————————

-9.8m/s2

= -9m/s

—————-

-9.8m/s2

=0.92s