Eddie set up a science experiment with plants. He bought three small tomato plants, all about the same size and height, and set
1 answer:
You might be interested in
To solve this problem we are going to use tow kinematic equations for falling objects.
1. Kinematic equation for final velocity:
where
is the final velocity
is the initial velocity
is the acceleration due to gravity 
is the time
2. Kinematic equation for distance:
where
is the distance
is the initial velocity
is the final velocity
is the acceleration due to gravity
is the time
First, we are going to convert 21.82 mi/h to ft/s:
Next, we are going to use the first equation to find how long it takes for the rock to reach its maximum height.
We know for our problem that the object is thrown in upward direction, so its velocity at its maximum height (before falling again) will be zero; therefore:
. We also know that it initial speed is 31.21 ft/s, so 
. Lets replace those values in our formula to find :
seconds
Next, we are going to use that time in our second kinematic equation to find the distance the object reach at its maximum height:
ft
Now we can add the height of the building and the maximum height of the object:
ft
Next, we are going to use that height (distance) in our second kinematic equation one more time to fin how long it takes for the object to fall from its maximum height to the ground:
or 
Since time cannot be negative,
is the time it takes the object to fall to the ground.
Finally, we can use that time in our first kinematic equation to find the final speed of the object when it hits the ground:
ft/s
We can conclude that the speed of the object when it hits the ground is 110.25 ft/s
1. Kinematic equation for final velocity:
where
2. Kinematic equation for distance:
where
First, we are going to convert 21.82 mi/h to ft/s:
Next, we are going to use the first equation to find how long it takes for the rock to reach its maximum height.
We know for our problem that the object is thrown in upward direction, so its velocity at its maximum height (before falling again) will be zero; therefore:
Next, we are going to use that time in our second kinematic equation to find the distance the object reach at its maximum height:
Now we can add the height of the building and the maximum height of the object:
Next, we are going to use that height (distance) in our second kinematic equation one more time to fin how long it takes for the object to fall from its maximum height to the ground:
Since time cannot be negative,
Finally, we can use that time in our first kinematic equation to find the final speed of the object when it hits the ground:
We can conclude that the speed of the object when it hits the ground is 110.25 ft/s
A) The resultant force is 30.4 N at
B) The resultant force is 18.7 N at
Explanation:
A)
In order to find the resultant of the two forces, we must resolve each force along the x- and y- direction, and then add the components along each direction to find the components of the resultant.
The two forces are:
at
above x-axis
at
above y-axis
Resolving each force:
So, the components of the resultant are:
And the magnitude of the resultant is:
And the direction is:
B)
In this case, the 15 N is applied in the opposite direction to the 20 N force. Therefore we need to re-calculate its components, keeping in mind that the angle of the 15 N force this time is
So we have:
So, the components of the resultant this time are:
And the magnitude is:
And the direction is:
Learn more about vector addition:
#LearnwithBrainly