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The average velocity of an object moving along a straight line is always as big as its instantaneous velocity?
Not at all. If it slows down or speeds up at any point, then it'll have different instantaneous
velocity at different points, and its average velocity for some section of the line can be yet
another different number.
Simple example:
A guy drives home from the office at a steady speed of 35 miles per hour.
On the way, he stops buy a soda.
His instantaneous velocity is zero during the stop, and 35 miles per hour
whenever he's moving.
His average velocity for the trip home is more than zero, and less than 35 miles per hour.
What else can I help you with?
When is speed equal to the magnitude of velocity?
Speed is equal to the magnitude of velocity when the object is moving in a straight line without changing direction. In other words, if the velocity vector is pointing in the same direction as the motion of the object, then the speed will be equal to the magnitude of the velocity.
Is the average speed equal to the magnitude of the average velocity justify your answer?
Yes usually and no rarely, velocity is defined as a vector, having both a direction and a magnitude (which is speed in the case of velocity). For instance 100 mph (speed) east (0o) (direction). In this form it is easy to see that the magnitude is 100 mph but mathematically to determine the magnitude of a vector you would divide the vector by its direction. 100 mph 0o / 0o = 100 mph Average speed and average velocity share the same relationship as instantaneous speed and instantaneous velocity so divide out the average direction from your average velocity to determine your average speed. If this is over a time period and you know the beginning and ending places in space your averages will simply be the difference from the starting to the ending places. So yes so long as you define speed to actually be the magnitude of the vector. However, if speed is taken without direction over time it may become something different. If an object travels along a vector with a negative magnitude its speed will not be negative but its vector magnitude will. Ex: A car travelling in reverse still has a positive speed but a compass will show it to be heading in the opposite direction of travel, a negative vector value...
Why average velocity of molecules of a gas is zero but the square of average velocity is not zero?
It depends on the sign of velocities. For example, if there are two velocities 7 and -7 m/s then the average velocity of the molecules will be 0. But, the square will be 49. The general thing here is that even if a velocity is negative, the square of EVERY velocity irrespective of the sign is positive i.e., squaring always removes the negative sign.
Why average velocity of molecules in gas zero whereas the average square of velocity is not zero?
Because squaring a velocity removes its sign. A velocity may be negative, but it's square is always positive. If two velocities are +5 and -5, their average is zero. But both squares are +25, so the average square is +25.
Average velocity always equals one-half the sum of the initial and final velocities?
Is this a question? or a statement that you are unsure of? Well anyways, this would be correct if acceleration was a constant but if acceleration is not a constant, the (not-constant) acceleration would change the rate of velocity and thus that statement/question would be false.
Is instantaneous velocity a vector or a scalar?
Instantaneous velocity is a vector quantity because it has both magnitude and direction. It describes the rate at which an object changes its position in a specific direction at a given moment in time.
When is speed equal to the magnitude of velocity?
Speed is equal to the magnitude of velocity when the object is moving in a straight line without changing direction. In other words, if the velocity vector is pointing in the same direction as the motion of the object, then the speed will be equal to the magnitude of the velocity.
How does average velocity differ from instsntaneous velocity?
If a 5 mile stretch of a bus journey lasts 15 minutes, then the average speed over this stretch was 20mph. But undoubtedly the bus achieved greater speeds than this, and it also spent time sitting still in queues. So the simple answer to the question is 'yes'. Less trivially and more interestingly: unless velocity is actually constant, then an object's average velocity over a finite time interval - and hence any empirical measurement of its speed - must (nearly always) differ from the instantaneous velocity. As the time period grow closer to zero, the measured velocity will converge on the instantaneous figure, but will never reach it.
Is numerical ratio of average velocity to average speed always equal?
No, the numerical ratio of average velocity to average speed is not always equal. Average velocity is a vector quantity that includes both magnitude and direction, while average speed is a scalar quantity that only considers magnitude. The ratio will be equal only when the object moves in a straight line.
Does the position-time graph of an object moving with a constant average velocity is always a straight line?
yes
Consider the instantaneous velocity of a body this velocity is always in the direction of what the net force at that instant the least resistance at that instant or the motion at that instant?
The instantaneous velocity of a body is always in the direction of the resultant force acting on it at that instant. It is influenced by the net force and not necessarily by the least resistance or the current motion of the body.
When is the average velocity equal to average of velocity for an object?
Always.
How can you obtain the average velocity and instantaneous velocity from a displacement time graph?
You cannot because a dispacement-time graph is concerned only with motion in a radial direction; any motion in a transverse direction is completely ignored. For example, an object circling the origin at a fixed distance, even with a variable speed, is always at the same distance from the origin. So the displacement-time graph will be a straight line whose height is the radial distance. A straight line in the distance-time graph is to be interpreted as no motion! Really?!The average velocity in the radial direction is the final displacement minus the starting [initial] displacement, all divided by the difference in time between the two points. The instantaneous velocity in the radial direction is the slope [gradient] of the graph at the point in question.
Is the magnitude of instantaneous velocity always equal to the instantaneous speed?
Because speed is the magnitude of the velocity vector. The velocity consists of the speed and the direction, and the whole thing can be embodied in a 3D vector. If you like the velocity is the magnitude (the speed), which is a scalar (just a real number), multiplied by a unit vector in the right direction.
What is the difference between Instantaneous speed and instantaneous velocity?
Speed has only size. Velocity has size and direction.If three drivers are driving their cars at 50 mph headed north, 50 mph headed south, and50 mph headed east, their speeds are all equal, but their velocites are all different.Instantaneous speed is the speed at an instant in time. A point on the edge of an LP record hasthe same instantaneous speed whenever you look at it.Instantaneous velocity is the velocity ... speed and direction ... at an instant in time. A point on theedge of an LP record has a different instantaneous velocity every time you look at it. Even thoughthe speed is always the same, the direction keeps changing.
Can you say that the average speed is always less than the instantaneous speed example?
donkeys is the clue
Are average speed and average velocity always the same measurements why?
I think it is cuz speed is velocity it's just a vector (more difficult name)
