Answer:
87.5 m/s
Explanation:
The speed of a wave is given by

where
v is the wave speed
is the wavelength
f is the frequency
In this problem, we have
is the frequency
is the wavelength
Substituting into the equation, we find

Answer:
, repulsive
Explanation:
The magnitude of the electric force between two charged particles is given by Coulomb's law:
where:
is the Coulomb's constant
are the two charges of the two particles
r is the separation between the two charges
The force is:
- repulsive if the two charges have same sign
- Attractive if the two charges have opposite signs
In this problem, we have two electrons, so:
is the magnitude of the two electrons
is their separation
Substituting into the formula, we find the electric force between them:

And the force is repulsive, since the two electrons have same sign charge.
Answer:
Average speed equals distance / time
380 / 40 = 9.5 m/s.
Explanation:
In the thermal equilibrium, the change in temperature is said to be zero in between the bodies. Thermal equilibrium is reached when both objects have the same temperature.
<h3>What is thermal equilibrium?</h3>
Thermal equilibrium is easily explained by the zeroth law of thermodynamics. If any two-body is at thermal equilibrium there is no change in the temperature of the body.
According to zeroth law if body A is in thermal equilibrium with body B and body B is in thermal equilibrium with C . So body A and C are also in thermal equilibrium.
In the thermal equilibrium, the net heat transfer is said to be zero in between the bodies.
Hence option A IS RIGHT. Thermal equilibrium is reached when both objects have the same temperature
To learn more about the thermal equilibrium refer to the link;
brainly.com/question/2637015