Answer: 4
The mechanical advantage is the ratio of the force exerted by the object to the force applied to do work on it.
Here, Jeff tried to lift a rock weighing 600 pounds by wedging board under the rock. Jeff who weighs 150 pounds uses all his weight to exert force on lever and lift rock.
Mechanical advantage, 
Therefore, the mechanical advantage that lever provided to Jeff in lifting rock is 4.
Answer:
Lift is the upward force on the wing acting perpendicular to the relative wind and perpendicular to the aircraft's lateral axis. Lift is required to counteract the aircraft's weight.
Explanation:
Answer:
D) This is the correct answer
Explanation:
In this exercise the two ball loads are suspended by a thread.
To answer this exercise, let us remember that charges of the same sign repel and charges of a different sign attract.
Therefore, for the system to maintain equilibrium, the two charges must be of the same sign.
When examining the different proposals
A) in this case, as a sphere has no charge, there is no electric force and the induced charge is of the opposite sign, so the spheres attract each other
B) in this case there is an electric force, but being of a different sign, the force is attractive so the system is not in equilibrium
C) as the charges are of different magnitude the system does not have equal angles
D) This is the correct answer, since the charges have the same magnitude and are of the same sign, so the force is repulsive and is counteracted by the weight component
F_e = W sin θ
Answer:
Explanation:
Since <em>light is so fast</em> we can assume no time passes between the lightning strikes and we observe it. We want to know then how far away did the strike occur for the sound to take 16s to reach our ears. Since the definition of velocity tells us that 
, we can write 
