Answer:
B) The tree was stationary and began to move.
Explanation:
This situation can be explained by using Newton's first law of motion, which states that
"An object at rest (or in motion at constant velocity) stays at rest (or in motion at constant velocity) unless a net non-zero force is exerted on it"
This means that an object at rest can start moving if and only if there is a net non-zero force acting on it.
In the example in the problem, the tree is initially stationary. Later, it started to move. According to Newton's first law, therefore, there must be a net force that caused this change of state of motion of the tree. Therefore, the correct answer is
B) The tree was stationary and began to move.
Well....t usually stands for time and the unit seconds proves that
Answer:
V = x/t
where:
x = distance [m]
t = time [s]
V = velocity [m/s]
Explanation:
Speed is defined as the distance travelled by a body in a given time interval. The velocity or speed is a vector, that is, it has magnitude and direction.
By virtue of its vector character, the direction of the displacement and the module, which is called speed, must be considered to define the velocity.
<u>Average speed</u>
The average speed is defined as the change of position over a given time interval. It is calculated by dividing the displacement vector (Δx) between the time interval (Δt) used.
<u>Instant speed</u>
Instantaneous velocity is a vector tangent to the trajectory, corresponding to the derivative of the vector position relative to time.
It allows to know the speed of a mobile that moves on a trajectory when the interval of time is infinitely small, being then the space traveled also very small, representing a point of the trajectory. Instant velocity is always tangent to the trajectory.
