Answer: option 1. thermal expansion and contraction.
The thermostat uses the thermal expansion and contraction of metals: when the metal expands it acts as a switch, a coiled ribbon expands and the electric circuit is off, then the current stops. When the temperatures decrease, the coiled ribbon contracts and the circuit is on, then the current starts to flow and the resistance starts to radiate heat.
Answer:
v = 8.57 m/s
Explanation:
As we know that the wagon is pulled up by string system
So the net force on the wagon along the inclined is due to tension in the rope and component of weight along the inclined plane
So as per work energy theorem we know that
work done by tension force + work done by force of gravity = change in kinetic energy
so we have
m = 38.2 kg
d = 85.4 m
so now we have
Answer:
Explanation:
The force exerted between two current-carrying wires is given by
where
is the vacuum permeability
I1 and I2 are the two currents
L is the length of the segment of wire on which we want to calculate the force
r is the distance between the wires
In this problem we have:
Substituting into the formula, we find:
And since the direction of the two currents is opposite, the force between the wires is repulsive.