If the crate is moving along the floor in the same direction with a constant speed, it is in dynamic equilibrium. Equilibrium means there is no net force acting on the crate.
Since there is no net force on the crate, there must be a friction force on the crate equal in magnitude and opposite in direction to the applied horizontal force. Therefore the force of friction acting on the crate is 100N.
Answer:
83.2 W/m^2
Explanation:
The radiation per unit area of a star is directly proportional to the power emitted, which is given by Stefan-Boltzmann law:

where
is the Stefan-Boltzmann constant
A is the surface area
T is the surface temperature
So, we see that the radiation per unit area is proportional to the fourth power of the temperature:

So in our problem we can write:

where
is the power per unit area of the present sun
is the temperature of the sun
is the power per unit area of sun X
is the temperature of sun X
Solving for I2, we find

Answer:
The direction of these oscillations is the difference between longitudinal or transverse waves. In longitudinal waves, the vibrations are parallel to the direction of wave travel. In transverse waves, the vibrations are at right angles to the direction of wave travel.
Explanation: