Answer:
h = 38.41 m
Explanation:
Given that,
A ball is thrown horizontally from the top of a building and strikes the sidewalk after 2.8 s.
We need to find the height of the building. Let it is h.
Initial speed of the ball, u = 0
Using second equation of motion to find h as follows :
So, the building is 38.41 m tall.
Answer:
14 N to the right
Explanation:
The net force is equal to the resultant of the forces acting on the wagon. In this case, we are considering two forces acting on the wagon:
- The force applied by Marybeth, to the left, of magnitude 34 N
- The force applied by Grant, to the right, of magnitude 48 N
Since the two forces are in opposite directions, in order to find the net force, we must choose a positive direction. Let's take "right" as positive direction, so the net force is:
And the positive sign means the net force is to the right. Due to this net force different from zero, the wagon will have an acceleration to the right, so if the wagon was at rest, it will start moving to the right.
Let's start by finding the time it takes for the dog to reach a velocity of m/s.
We can use the following equation, where is initial velocity,
is final velocity,
is time, and
is acceleration.
We're trying to solve for first, so divide both sides by
.
Substitute in the known values.
Now, we can use the following formula to find the distance.
Substitute in the known values.
Anything multiplied by is
Just simplify from there.