The load is the weight of the rock that Jonathan lifts:

The effort instead is the force applied in input to the lever in order to lift the rock:

So, the ratio between load and effort for this exercise is

So, the ratio is 10:1.
The wires would remain attracted to each other.
Option D.
Explanation:
It is known that magnetic flux will be generated in conductors with varying emf. So when current is flowing in two parallel conductors, the magnetic flux will be generated in those wires. If the current is flowing in same direction in both the wires, then the magnetic flux will be generated towards inside and outside the wires. Thus, the wire will get attracted to each other till the time the current is flowing in the same direction in both the wires. So if the current flow in each wire was reversed at the same time, then the wire would remain attracted to each other.
The correct answer among the choices given is the last option. Cora wrapping the copper wire with a thick plastic coating keeps a current from passing out a wire. The plastic wire here serves as an insulator. An insulator is a material that prevents electricity or current to flow out the circuit. In order to lessen the loss of energy.
HOPE THIS HELPS!
Answer:
light
Explanation:
Light is part of a spectrum of electromagnetic energy that includes radio waves, microwaves, infrared radiation, visible light, ultraviolet "light", x rays, and gamma rays.
E = hf
E : photon energy
h : Plank's constant 6.63×10^-34
f : frequency
Hope it helped!