Is it possible to have a negative average velocity

Notice, however, that the direction can be omitted until the end to avoid cluttering the problem. Pay attention to the significant figures in the problem. The distance m has three significant figures, but the time interval s has only two, so the quotient should have only two significant figures.

Note the way scalars and vectors are represented. In this book d represents distance and displacement. Similarly, v represents speed, and v represents velocity. A variable that is not bold indicates a scalar quantity, and a bold variable indicates a vector quantity. Vectors are sometimes represented by small arrows above the variable.

Use this problem to emphasize the importance of using the correct number of significant figures in calculations. Some students have a tendency to include many digits in their final calculations.

They incorrectly believe they are improving the accuracy of their answer by writing many of the digits shown on the calculator. Point out that doing this introduces errors into the calculations. In more complicated calculations, these errors can propagate and cause the final answer to be wrong.

Instead, remind students to always carry one or two extra digits in intermediate calculations and to round the final answer to the correct number of significant figures. Layla jogs with an average velocity of 2. What is her displacement after 46 seconds? We know that Layla's average velocity is 2. We can rearrange the average velocity formula to solve for the displacement.

The answer is about m east, which is a reasonable displacement for slightly less than a minute of jogging. A calculator shows the answer as We chose to write the answer using scientific notation because we wanted to make it clear that we only used two significant figures. Dimensional analysis is a good way to determine whether you solved a problem correctly. Write the calculation using only units to be sure they match on opposite sides of the equal mark.

Phillip walks along a straight path from his house to his school. How long will it take him to get to school if he walks m west with an average velocity of 1.

We know that Phillip's displacement is m west, and his average velocity is 1. We can calculate the time required for the trip by rearranging the average velocity equation.

Here again we had to use scientific notation because the answer could only have two significant figures. Since time is a scalar, the answer includes only a magnitude and not a direction.

A bird flies with an average velocity of 7. It then pauses before flying with an average velocity of 6. In this simulation you will put your cursor on the man and move him first in one direction and then in the opposite direction. Keep the Introduction tab active. You can use the Charts tab after you learn about graphing motion later in this chapter. Carefully watch the sign of the numbers in the position and velocity boxes.

Ignore the acceleration box for now. Then see if you can do the opposite. This is a powerful interactive animation, and it can be used for many lessons. At what time is the instantaneous velocity equal to the average velocity? What is the greatest example of an instantaneous speed? What is instantaneous speed give example? When can the speed and average speed of a vehicle be equal? Why velocity is scalar? What is speed acceleration and velocity? Previous Article Are there 6 or 7 universal emotions?

So I would say that between 10 and 20 the average velocity is the greatest. All Calculus videos Unit The Derivative. Previous Unit Limits and Continuity. Next Unit Techniques of Differentiation. Norm Prokup. Explanation Transcript To find where the average velocity of an object is positive or negative, simply find slopes between the given points these points will be the time at which an object is at a certain position.

Calculus The Derivative. Science Biology Chemistry Physics. Speed is the magnitude of the velocity vector, so it can never be negative.

Any scalars that are defined as the magnitude of a vector is non-negative. But, there are some scalars that can be negative. If a scalar can be represented on a number line, then it is a real number, and both positive, and negative numbers, and zero. An object which moves in the positive direction has a positive velocity.

If the object is slowing down then its acceleration vector is directed in the opposite direction as its motion in this case, a negative acceleration.

Assuming rightward is positive, the velocity is positive whenever the car is moving to the right, and the velocity is negative whenever the car is moving to the left. The acceleration points in the same direction as the velocity if the car is speeding up, and in the opposite direction if the car is slowing down. Yes, it is possible If an object is moving and it slows down the acceleration acts opposite to it.

Consider an cycle moving towards northward but when the brakes are applied it slows down so acceleration acts in opposite direction southward acceleration.

Yes , when brakes are applied to a cycle moving northward. At that instant, it has a northward velocity and a southward acceleration. No , it is not possible because the velocity and acceleration both should be in one direction then only movement of cycle is possilble or else cycle will not move. Yes, an object can be moving at the same time that it is also slowing down.