Complete Question
An airplane takes off a runway at a constant speed of 49 m/s at constant angle 30 to the horizontal.How high (in meters ) is the airplane above the ground 13 seconds after takeoff?
Answer:
The height is ![H = 318.5 \ m](https://tex.z-dn.net/?f=H%20%20%3D%20%20318.5%20%5C%20m)
Explanation:
From the question we are told that
The speed at which the plane takes off is ![u = 49 \ m/s](https://tex.z-dn.net/?f=u%20%3D%2049%20%5C%20m%2Fs)
The angle at which it takes off is ![\theta = 30 ^o](https://tex.z-dn.net/?f=%5Ctheta%20%20%3D%20%2030%20%5Eo)
The time taken is ![t = 13 s](https://tex.z-dn.net/?f=t%20%3D%20%2013%20%20s)
The vertical distance traveled is mathematically represented as
![H = u sin \theta t](https://tex.z-dn.net/?f=H%20%20%3D%20%20u%20sin%20%20%5Ctheta%20%20t)
Substituting values
![H = (49) * sin (30) *13](https://tex.z-dn.net/?f=H%20%20%3D%20%20%2849%29%20%2A%20sin%20%2830%29%20%2A13)
![H = 318.5 \ m](https://tex.z-dn.net/?f=H%20%20%3D%20%20318.5%20%5C%20m)
Answer:
Studies show that eating fewer animal-based products could reduce water use since animal production uses more water than crops do. In addition, reducing the amount of food that's lost or wasted at various points in the food supply chain could feed about 1 billion extra people while simultaneously reducing water use.
Initial velocity (Vi) = 25 m/s
acceleration (a) = ![-4 m/s^{2}](https://tex.z-dn.net/?f=-4%20m%2Fs%5E%7B2%7D)
time interval (t) = 5 sec
let us assume that final velocity after 5 sec be Vf
As acceleration is constant, we can apply the the equation of motion with constant acceleration i.e. ![V_{f} = V_{i} + at](https://tex.z-dn.net/?f=V_%7Bf%7D%20%3D%20V_%7Bi%7D%20%2B%20at)
Hence, ![V_{f} = 25 +(-4)(5) = 25 -20 = 5 m/s](https://tex.z-dn.net/?f=V_%7Bf%7D%20%3D%2025%20%2B%28-4%29%285%29%20%3D%2025%20-20%20%3D%205%20m%2Fs)
so, the velocity of bicyclist will be 5 m/s after 5 sec
what are the answer choices?