Conceptual Physics Ch.3 Review Questions

A track is made from a piece of channel iron as shown. A ball released at the left end of the track continues past the various points. Rank the speeds of the ball at points A, B, C, and D, from fastest to slowest.

Three balls of different masses are thrown straight upward with initial speeds as indicated. From fastest to slowest, rank the speeds of the balls 1s after being thrown. From greatest to least, rank the accelerations of the balls 1s after being thrown- or are the accelerations the same?

Here we see top views of three motor boats crossing a river. All have the same speed relative to the water, and all experience the same river flow. Construct resultant vectors showing the speed and direction of each boat. Rank the boats from most to least for a) the time to reach the opposite shore b) the fastest ride. (I will send picture). We have absolutely no clue how to do this.

Jo, with a reaction time of 0.2 seconds, rides her bike at a speed of 6.0 m/s. She encounters an emergency situation and immediately applies her brakes. How far does Jo travel before she actually applies the brakes?

Suzie Surefoot can paddle a canoe in still water at 8 km/h. How successful will she be canoeing upstream in a river that flows 8 km/h?

One airplane travels due north at 300km/h while another travels due south at 300 km/h. Are their speeds the same? Are their velocities the same?

You're traveling in a car at some specified speed limit. You see a car moving at the same speed coming toward you. How fast is the car approaching you, compared with the speed limit?

Jacob says acceleration is how fast you go. Emily says acceleration is how fast you get fast. They look to you for confirmation. Who is correct?

What is the acceleration of a car that moves at a steady velocity of 100 km/h for 100s?

Galileo experimented with balls rolling on inclined planes for various angles. What is the range of accelerations from angles 0 degrees to 90 degrees? From what acceleration to what? I didn't know how to do this one.

Suppose that a freely falling object in the preceding exercise were also equipped with an odometer. Would the readings of distance fallen each second indicate equal or different falling distances for successive seconds?

If air resistance can be ignored, how does the acceleration of a ball that has been tossed straight upward compare with its acceleration if simply dropped?

Boy Bob stands at the edge of a cliff and throws a ball nearly straight up at a certain speed and another ball nearly straight down with the same initial speed. If air resistance is negligible, which ball will have the greater speed when it hits the ground below?

While rolling balls down an inclined plane. Galileo observes that the ball rolls 1 cubit as he counts to 10. How far will the ball have rolled from its starting point when he has counted to 20?

As speed increases for an object in free fall, does acceleration increase also?

Why would a person's hang time be considerably greater on the Moon than on Earth?

Vertically falling rain makes slanted streaks on the side of windows of a moving automobile. If the streaks make an angle of 45 degrees, how does the speed of the automobile compare with the speed of the falling rain?

Make up a multiple choice question that would check a classmate's understanding of the distinction between velocity and acceleration.

Can an object reverse its direction of travel while maintaining a constant acceleration? If so, cite an example to your classmates. If not, provide an explanation.

Correct your friend who says, "The dragster rounded the curve at a constant velocity of 100 km/h!"

Cite an instance when your speed could be zero while your acceleration is a nonzero.

a) Can an object be moving when its acceleration is zero? If so, give an example. B) Can an object be accelerating when its speed is zero? If so, give an example.

On which of these hills does the ball roll down with increasing speed and decreasing acceleration along the path?

Be picky and correct your friend who says, "in free fall, air resistance is more effective in slowing a feather than a coin."

In the preceding exercise can you think of a reason why the acceleration of the object thrown downward through the air might be appreciably less than 10 m/s squared?

Madison tosses a ball straight upward. Anthony drops a ball. Your discussion partner says that both balls undergo the same acceleration. What is your response?

Refer to the pair of tracks in the preceding exercise. A) On which track is the average speed greater? B) Why are the speeds of the balls at the ends of the track the same?

If rain drops fall vertically at a speed of 3 m/s and you are running horizontally running at 4 m/s convince your classmates that the drops will hit your face at a speed of 5 m/s.

In this chapter, we studied idealized cases of balls rolling down smooth planes and objects falling with no resistance. Suppose a classmate complains that all this attention focused on idealized cases is worthless because idealized cases don't simply occur in everyday world. How would you respond to this complaint? How do you suppose the author of this book would respond?