Answer:
![y = 4.36](https://tex.z-dn.net/?f=y%20%3D%204.36)
Explanation:
Let the height of the ladder be L
![L = 10](https://tex.z-dn.net/?f=L%20%3D%2010)
Also:
- Let
![x = distance\ from\ the\ base\ of\ the\ ladder](https://tex.z-dn.net/?f=x%20%3D%20distance%5C%20from%5C%20the%5C%20base%5C%20of%5C%20the%5C%20ladder)
- Let
![y = height\ of\ the\ base\ of\ the\ ladder](https://tex.z-dn.net/?f=y%20%3D%20height%5C%20of%5C%20the%5C%20base%5C%20of%5C%20the%5C%20ladder)
When the ladder leans against the wall, it forms a triangle and the length of the ladder forms the hypotenuse.
So, we have:
--- Pythagoras Theorem
When the base is 9ft from the wall, this means that:
![x = 9](https://tex.z-dn.net/?f=x%20%3D%209)
Substitute 9 for x and 10 for L in ![L^2 = x^2 + y^2](https://tex.z-dn.net/?f=L%5E2%20%3D%20x%5E2%20%2B%20y%5E2)
![10^2 = 9^2 + y^2](https://tex.z-dn.net/?f=10%5E2%20%3D%209%5E2%20%2B%20y%5E2)
![100 = 81 + y^2](https://tex.z-dn.net/?f=100%20%3D%2081%20%2B%20y%5E2)
Make
the subject
![y^2 = 100 - 81](https://tex.z-dn.net/?f=y%5E2%20%3D%20100%20-%2081)
![y^2 = 19](https://tex.z-dn.net/?f=y%5E2%20%3D%2019)
Make y the subject
![y = \sqrt{19](https://tex.z-dn.net/?f=y%20%3D%20%5Csqrt%7B19)
![y = 4.36](https://tex.z-dn.net/?f=y%20%3D%204.36)
<em>Hence, the true distance at that point is approximately 4.36ft</em>
Answer:
T= 5.18N
Explanation:
u = mass of chord / length of chord
u = 0.49/ 7.3
u = 0.067 kg/m
Velocity of sound waves (v) =length of chord / time taken for wave to travel
v = 7.3 / 0.83 = 8.795m/s
Tension is calculated below using the formula
T = v² * u
T = (8.795)² x 0.067
T= 5.18N
Answer:
Also 3s.
Explanation:
Each component is independent in two dimensional motion. This means that <em>how much time does something take to reach the ground when dropped is independent from any horizontal velocity</em>. If at one run a drop lasts 3s, at another run with twice the (horizontal) velocity and same height will also last 3s, no matter what.
Answer:
Vy = V sin theta = 30 * ,574 = 17.2 m/s
t1 = 17.2 / 9.8 = 1.76 sec to reach max height
Max height = 17.2 * 1.76 - 1/2 * 4.9 * 1.76^2 = 15.1 m
H = V t - 1/2 g t^2 = 1.2 * 9.8 * 1.76^2 = 15.1 m
Time to fall from zero speed to ground = rise time = 1.76 sec
Vx = V cos 35 = 24.6 m / sec horizontal speed
Time in air = 1.76 * 2 = 3.52 sec before returning to ground
S = 24.6 * 3.52 = 86.6 m