# Motion

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6. A car starts from Hither, goes 50 km in a straight line to Yon, immediately turns around and returns to Hither. The time for this round trip is 2 hours. THe magnitude of the avearge velocity of the car for this round trip is:

7. A car starts from Hither, goes 50 km in a straight line to Yon, immediately turns around and returns to Hither. The time for this round trip is 2 hours. THe magnitude of the avearge speed of the car for this round trip is:

8. The coordinate of a particle in meters is given by x(t) = 16t - 3.0t^3, where the time t is in seconds. The particle is momentarilly at rest at t =

9. A drag racing car starts from rest at t = 0 and moves along a straight line with velocity given by v= bt^2, where b is a consant. The expressoin for the distance traveled by this car from its position at t = 0 is:

10. A ball rolls up a slope. At the end of three seconds its velocity is 20 cm/s; at the end of eight seconds its velocity is 0. What is the avearge acceleration from the third to the eighth second?

11. The coordinate of an object is given as a function of time by x = 7t - 3t^2, where x is in meters and t is in seconds. Its avearge velocity over the interval from t =0 to t = 4s is

12. The velocity of an object is given as a function of time by v = 4t - 3t^2, where v is in m/s and t is in seconds. Its avearge velocity over the interval from t =0 to t = 2s is

13. The coordinate of an object is given as a function of time by x = 4t^2 - 3t^3, where x is in meters and t is in seconds. Its avearge acceleration over the interval from t =0 to t = 2s is

16. An object starts from rest at the origin and moves along the x axis with a constant acceleration of 4 m/s^2. Its average velocity as it goes from x = 2m to x = 8m is

20. The position y of a particle moving along the y axis depends on the time t according to the equation y = at - bt^2. The dimensions of the quantities a and b are respectively:

22. Over a short interval near time t =0 the coordinate of an automobile in meters is given by x(t) = 27t - 4.0t^3, where t is in seconds. At the end of 1.0 s the acceleration of the auto is

23. Over a short interval near time t =0 the coordinate of an automobile in meters is given by x(t) = 27t - 4.0t^3, where t is in seconds. The magnitude of the initial velocity and acceleration of the auto respectively are

24. At time t = 0 a car has a velocity of 16 m/s. It slow down with an acceleration given by -0.50t, in m/s^2 for t seconds. It stops at t =

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6. The average velocity is the displacement over the total time. Since the car returns to the starting point, the displacement is zero. So the average velocity is zero.

7. The average speed is the distance traveled over the total time.

Distance=50+50=100 km.

Total time=2 hr

The average speed=100 km/ 2 h=50 km/h

8.

The velocity is

When the particle is momentarily at rest

The time is 1.3 seconds.

9. The distance

10.

11. At t=0, x=0

At t=4s,

So the average velocity is

12. To calculate the average velocity, the displacement change needs to be calculated first.

At t=0, d=0;

At t=2,

The ...

#### Solution Summary

It provides detailed explainations to motion related questions.