Your answer is c hope I helped
Answer:
F = 51 10² N and The force applied is 11.6 times greater than the weight
Explanation:
As we are asked the force we can use Newton's second law and we calculate the acceleration by kinematics
y = v₀ t + ½ a t²
On the ground its initial velocity is zero (v₀ = 0)
y = ½ a t²
a = 2y / t²
a = 2 2.5 / 0.21²
a = 113.38 m / s²
We calculate the force
F = ma
F = 45 113.38
F = 5102 N
F = 51 10² N
For the relationship of this force with the weight, divide the two
F / W = 51 10²/45 9.8
F / W = 11.6
The force applied is 11.6 times greater than the weight
Answer:
22.27 m
Explanation:
initial velocity, u = 25 m/s
Angle of projection, θ = 45°
height, h = 30 m
Let t be the time taken to reach the ground.
use second equation of motion in vertical direction
![s = ut + \frac{1}{2}at^{2}](https://tex.z-dn.net/?f=s%20%3D%20ut%20%2B%20%5Cfrac%7B1%7D%7B2%7Dat%5E%7B2%7D)
![- 30 = -25 Sin 45\times t - \frac{1}{2}\times 9.8t^{2}](https://tex.z-dn.net/?f=-%2030%20%3D%20-25%20Sin%2045%5Ctimes%20t%20-%20%5Cfrac%7B1%7D%7B2%7D%5Ctimes%209.8t%5E%7B2%7D)
![4.9t^{2}+17.67 t - 30 = 0](https://tex.z-dn.net/?f=4.9t%5E%7B2%7D%2B17.67%20t%20-%2030%20%3D%200)
![t=\frac{-17.67\pm \sqrt{17.67^{2}+4\times 4.9 \times 30}}{9.8}](https://tex.z-dn.net/?f=t%3D%5Cfrac%7B-17.67%5Cpm%20%5Csqrt%7B17.67%5E%7B2%7D%2B4%5Ctimes%204.9%20%5Ctimes%2030%7D%7D%7B9.8%7D)
t = 1.26 second
The horizontal distance = horizontal velocity x time
d = 25 Cos 45 x 1.26 = 22.27 m
You can calculate potential energy by:
U = m.g.h
Where, U = potential energy
m = mass
g = acceleration due to gravity
h = height
Hope this helps!