(a) The ball's height <em>y</em> at time <em>t</em> is given by
<em>y</em> = (20 m/s) sin(40º) <em>t</em> - 1/2 <em>g t</em> ²
where <em>g</em> = 9.80 m/s² is the magnitude of the acceleration due to gravity. Solve <em>y</em> = 0 for <em>t</em> :
0 = (20 m/s) sin(40º) <em>t</em> - 1/2 <em>g t</em> ²
0 = <em>t</em> ((20 m/s) sin(40º) - 1/2 <em>g t</em> )
<em>t</em> = 0 or (20 m/s) sin(40º) - 1/2 <em>g t</em> = 0
The first time refers to where the ball is initially launched, so we omit that solution.
(20 m/s) sin(40º) = 1/2 <em>g t</em>
<em>t</em> = (40 m/s) sin(40º) / <em>g</em>
<em>t</em> ≈ 2.6 s
(b) At its maximum height, the ball has zero vertical velocity. In the vertical direction, the ball is in free fall and only subject to the downward acceleration <em>g</em>. So
0² - ((20 m/s) sin(40º))² = 2 (-<em>g</em>) <em>y</em>
where <em>y</em> in this equation refers to the maximum height of the ball. Solve for <em>y</em> :
<em>y</em> = ((20 m/s) sin(40º))² / (2<em>g</em>)
<em>y</em> ≈ 8.4 m
Answer:
The cooling time will not be reduced.
Explanation:
The time to cook is virtually the same in both types, vigorously and gently boiling water.
The reason cooking of spaghetti calls for vigorously boiling water is to keep the pasta agitated so that they do not stick to one another.
The temperature of boiling water is the same for both vigorously boiling water and gently boiling water, therefore there will be little time difference in when the potatoes will cook when it is done with vigorously boiling water than when it is cooked with gently boiling water.
However cooking potatoes in vigorously boiling water may cause the water to dry up on time and the potatoes get burnt.
Answer:
sun, jupiter, earth, moon
Explanation:
how big they are
Answer:
We want to describe how to graph a linear equation.
Explanation:
The given equation is:
y = -4x - 1
a) To graph it, we need to find two points that belong to the line, then we graph the points, and then we connect them with a line.
To get the points, we just need to evaluate the function in two different values of x.
for x = 0
y = -4*0 - 1 = -1
So we have the point (0, -1)
for x = 1
y = -4*1 - 1 = -5
So we have the point (1, - 5)
Now we just need to find these two points and connect them with a line, the graph can be seen below.
b) To check if the graph is correct we can see two things:
in y = -4*x - 1
The y-intercept is -1, this means that the graph should intersect the y-axis at y = -1
The slope is -4, this means that for each unit increase on x, we should see that the y-value decreases by 4.
Checking those two things we can see if our graph is correct or not.
pls give brainliest!
