8.854 m/s is the speed of the box after it reaches bottom of the ramp.
<u>Explanation</u>:
From the figure we came to know that height of the block is 4 m.
We know that,
Total "initial energy of an object" = Total "final energy of an object
"
Total "initial energy of an object" is = "sum of potential energy" and "kinetic energy" of an object at its initial position.
Initial velocity is “0” as the object does not have starting speed
Total initial energy = 39.2 × m
Now, Total initial energy of an object = Total final energy of an object
Final speed is 8.854 m/s.
Answer:
The time he can wait to pull the cord is 41.3 s
Explanation:
The equation for the height of the skydiver at a time "t" is as follows:
y = y0 + v0 · t + 1/2 · g · t²
Where:
y = height at time "t".
y0 = initial height.
v0 = initial velocity.
t = time.
g = acceleration due to gravity (-9.8 m/s² considering the upward direction as positive).
First, let´s calculate how much time will it take for the skydiver to hit the ground if he doesn´t activate the parachute.
When he reaches the ground, the height will be 0 (placing the origin of the frame of reference on the ground). Then:
y = y0 + v0 · t + 1/2 · g · t²
0 m = 15000 m + 0 m/s · t - 1/2 · 9.8 m/s² · t²
0 m = 15000 m - 4.9 m/s² · t²
-15000 m / -4.9 m/s² = t²
t = 55.3 s
Then, if it takes 4.0 s for the parachute to be fully deployed and the parachute has to be fully deployed 10.0 s before reaching the ground, the skydiver has to pull the cord 14.0 s before reaching the ground. Then, the time he can wait before pulling the cord is (55.3 s - 14.0 s) 41.3 s.
Answer: Electromagnetism and sound
We have no way to say what the illustration represents, mainly because
you haven't given us a way to see the illustration.
<span>However, the process that all stars, including our sun, use to continuously
produce energy is nuclear fusion.</span>
