An 800 N man climbs 5 m up a ladder. How much gravitational potential energy does he gain?
1 answer:
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Answer:
130.5
Explanation:
According to the stemplot attached (Which I think it is, and if not, then you only need to replace the procedure with your data and you should be fine), you need to calculate first the points of all ten students. In that plot, we can easily calculate the points.
The first number in the colum represents the centen of the point, while the numbers of the second column, represents the units of that centen, for example if you see:
16 | 8 5 6
This means that the point for the students are 168, 165 and 166. Three students, three points.
If you watch the stemplot, the points for the students are:
116, 118, 121, 124, 128, 133, 137, 142, 146 and 179.
The median can be calculated using the mean between the two values in the middle of the sequence.
In this case, half of ten is 5, so, the numbers from the middle in this sequence are 128 and 133, therefore:
Median = 128 + 133 / 2 = 130.5
Part of the question is missing. Here it is:
<em>A 72 g autographed baseball slides off of a 1.3 m high table and strikes the floor a horizontal distance of 0.7m away from the table. The acceleration of gravity is 9.81 m/s2. What was the direction of the ball’s velocity just before it hit the floor? </em>
Answer:
Explanation:
The motion of the ball is a projectile motion, which consists of two separate motions:
- A horizontal motion at constant velocity
- A vertical motion at constant acceleration (free fall)
We start by analyzing the vertical motion, to find the time of flight of the ball. This can be done by using the suvat equation
where, choosing downward as positive direction:
s =1.3 m is the vertical displacement of the ball
u = 0 is the initial vertical velocity
is the acceleration of gravity
t is the time
Solving for t,
Now we can find the final vertical velocity of the ball, using:
And susbtituting t = 0.52 s, we find
It is important to keep in mind that the direction of this velocity is downward, since we chose downward as positive direction.
The horizontal velocity of the ball instead is constant; we know that the ball covers a horizontal distance of
d = 0.7 m
In a time of
t = 0.52 s
So, the horizontal velocity is
So now we can find the direction of the ball's velocity using:
And since the vertical direction is downward, this means that this velocity is below the horizontal, so the answer is