Answer:
As the temperature of materials increase, the objects find a phenomenon called change of phase.
This means that if you give enough heat to a liquid, this can change of state from liquid state to gas state (the water evaporates)
So the water in the pan reaches the evaporation temperature (around 100°C) and it starts to evaporate, this is why the water on the outside begins to "dry"
Answer:
The instantaneous velocity is the specific rate of change of position (or displacement) with respect to time at a single point (x,t) , while average velocity is the average rate of change of position (or displacement) with respect to time over an interval.Average velocity : Average velocity of a body is defined as the change in position or displacement (Δx) divided by time interval (Δt) in which that displacement occurs.
Instantaneous velocity : The instantaneous velocity of a body is the velocity of the body at any instant of time or at any point of its path .
velocity can be positive , negative or zero.
By studying speed and velocity we come to the result that at any time interval average speed of an object is equal or more than the average but instantaneous speed is equal to instantaneous velocity.
Actually Welcome to the Concept of the Kinematics.
1.) Distance travelled = 15+20 = 35 miles.
Ai the total distance covered is 35 miles.
2.) Displacement is the shortest distance from the initial point to the final point.
here it's ==> 20-15 = 5 miles
hence, displacement = 5 miles
