1.8 is the mechanical advantage of the lever.
<h3>Definition of mechanical advantage</h3>
The theoretical mechanical advantage of a system is the ratio of the force that performs the useful work to the force applied, assuming there is no friction in the system.
The advantage gained by the use of a mechanism in transmitting force specifically the ratio of the force that performs the useful work of a machine to the force that is applied to the machine.
Mechanical advantage is given by the ratio of the load lifted to the force applied to lift the load.
In this case, Mechanical advantage=L/E where L is the load and E is the effort applied.
Mechanical advantage= 90/50 =1.8
Question-you use a lever to lift a heavy tree branch. you apply a force of 50 n and the lever lifts the branch with a force of 90 n. what is the mechanical advantage of the lever?
To learn more about the Mechanical advantage visit the link
brainly.com/question/16617083
#SPJ4
Given that metal cases of electrical appliances are connected to the wire, let's select the statement which is not correct from the list of statements.
The earth wire is used to protect you and help reduce the risk of receiving an electric shock. The earth wire reduces the risk of electric shock by creating a path for a fault or lose current to flow to the Earth.
The Live wire may become loose and touch the metal case. In this case, the earth wire will channel the fault current to the earth thereby reducing the risk of electric shock.
If the metal case becomes live, the earth wire conducts current to the ground. This helps prevent electric shock from the metal case.
The Earth wire has low or no resistance. It is always made of copper.
It provides a low resistance path to the ground.
Therefore, the statement ''the earth wire needs to have high resistance'' is NOT current.
ANSWER:
C. The earth wire needs to have a high reistance.
Answer:
and 
Explanation:
The wavelength of a visible light is 727.3 nm.
The formula is as follows :
f is the frequency of the visible light
Energy of a photon is given by :
E = hf, h is Planck's constant
Red color has a frequency of 
and energy per photon is 
.
<span>assuming the pitch is 100yards long, the player runs 100yards to the other goal then a further 50 yards back to the 50-yard line. So he/she runs 150yards in 18s
150/18 = 8.33yards per second average speed.
Initial velocity = 0, average velocity =8.33
Vav = (Vinitial+Vfinal)/2
Vav = 4.16m/s</span>
