Answer:652.05 J
Explanation:
Given
Weight of lifter ![W=345 N](https://tex.z-dn.net/?f=W%3D345%20N)
vertical distance move ![h=1.89 m](https://tex.z-dn.net/?f=h%3D1.89%20m)
Work done in lifting the weight is equal change in Potential Energy of weight
Change in Potential Energy ![=m g h](https://tex.z-dn.net/?f=%3Dm%20g%20h)
![\Delta PE=345 \times 1.89=652.05 J](https://tex.z-dn.net/?f=%5CDelta%20PE%3D345%20%5Ctimes%201.89%3D652.05%20J)
therefore work done is equal to
Mechanical Waves require a medium to travel through in order to transport their energy from one location to another.
Hoped this helped!
Answer:
r = 2161.9 m
Explanation:
Aerodynamic lift(L) is perpendicular to the wing, which is tilted 40 degrees to the horizontal.
Since the plane is moving in a horizontal circle, the vertical component of the lift must cancel the weight W of the airplane, but the horizontal component is the centripetal force that keeps it in a circle.
L is perpendicular to wing at angle θ with respect to horizontal
Thus,
Vertical component of lift is:
L cosθ = W = mg
Thus, m = L cosθ / g - - - - (eq1)
Horizontal component of lift is:
L sinθ = centripetal force = mv² / r - - - - (eq2)
Combining equations 1 and 2,we have;
L sinθ = (L cosθ / g)(v² / r)
L cancels out on both sides to give;
tanθ = v²/ rg
r = v² / (g tanθ)
We are given;
velocity; v = 480 km/hr = 480 x 10/36 = 133.33 m/s
r = 133.33²/[(9.8) tan(40)] = 2161.9 m
Answer:
, where the minus indicates the direction is opposite to that of the throw.
Explanation:
a)
Since MKS stands for meter-kilogram-second and we know that:
![1\ hour = 3600\ seconds](https://tex.z-dn.net/?f=1%5C%20hour%20%3D%203600%5C%20seconds)
![1\ mile = 1600\ meters](https://tex.z-dn.net/?f=1%5C%20mile%20%3D%201600%5C%20meters)
![1000g = 1kg](https://tex.z-dn.net/?f=1000g%20%3D%201kg)
We can write that:
![\frac{1\ hour}{3600\ seconds}=1](https://tex.z-dn.net/?f=%5Cfrac%7B1%5C%20hour%7D%7B3600%5C%20seconds%7D%3D1)
![\frac{1600\ meters}{1\ mile}=1](https://tex.z-dn.net/?f=%5Cfrac%7B1600%5C%20meters%7D%7B1%5C%20mile%7D%3D1)
![\frac{1kg}{1000g}=1](https://tex.z-dn.net/?f=%5Cfrac%7B1kg%7D%7B1000g%7D%3D1)
These are conversion factors, equal to 1, so multiplying our results by them won't change their value, only their units.
So we have that:
![90 mph=90 \frac{miles}{hour}(\frac{1\ hour}{3600\ seconds})(\frac{1600\ meters}{1\ mile})=40m/s](https://tex.z-dn.net/?f=90%20mph%3D90%20%5Cfrac%7Bmiles%7D%7Bhour%7D%28%5Cfrac%7B1%5C%20hour%7D%7B3600%5C%20seconds%7D%29%28%5Cfrac%7B1600%5C%20meters%7D%7B1%5C%20mile%7D%29%3D40m%2Fs)
![110 mph=110 \frac{miles}{hour}(\frac{1\ hour}{3600\ seconds})(\frac{1600\ meters}{1\ mile})=48.89m/s](https://tex.z-dn.net/?f=110%20mph%3D110%20%5Cfrac%7Bmiles%7D%7Bhour%7D%28%5Cfrac%7B1%5C%20hour%7D%7B3600%5C%20seconds%7D%29%28%5Cfrac%7B1600%5C%20meters%7D%7B1%5C%20mile%7D%29%3D48.89m%2Fs)
![145 g=145 g(\frac{1kg}{1000g})=0.145kg](https://tex.z-dn.net/?f=145%20g%3D145%20g%28%5Cfrac%7B1kg%7D%7B1000g%7D%29%3D0.145kg)
b)
Newton's 2nd Law tells us that F=ma, and the definition of acceleration is
, so we have:
![F=m\frac{\Delta v}{\Delta t}=m\frac{v_f-v_i}{t}](https://tex.z-dn.net/?f=F%3Dm%5Cfrac%7B%5CDelta%20v%7D%7B%5CDelta%20t%7D%3Dm%5Cfrac%7Bv_f-v_i%7D%7Bt%7D)
Taking the throw direction as the positive one, for our values we have:
![F=m\frac{v_f-v_i}{t}=(0.145kg)\frac{(-48.89m/s)-(+40m/s)}{0.0007s}=-18412.9N](https://tex.z-dn.net/?f=F%3Dm%5Cfrac%7Bv_f-v_i%7D%7Bt%7D%3D%280.145kg%29%5Cfrac%7B%28-48.89m%2Fs%29-%28%2B40m%2Fs%29%7D%7B0.0007s%7D%3D-18412.9N)