Cracking the SAT Physics Subject Test

UNIFORM CIRCULAR MOTION In Chapter 2, we considered two types of motion: straight-line motion and parabolic motion. We will now ...

Since ∆v = v 2 − v 1 points toward the center of the circle (see the figure on the right), so does the acceleration, since a = ∆ ...

circular path of radius 2 m. Find the magnitude of the object’s acceleration and the net force responsible for its motion. Here’ ...

Work and Circular Motion All centripetal forces do no work, since the force is directed toward the center and the motion is tang ...

A roller-coaster car enters the circular-loop part of the ride. At the very top of the circle (where the people in the car are ...

In the previous example, if the net force on the car at its highest point is straight down, why doesn’t the car fall straight d ...

If the centripetal force acting on an object were suddenly removed, Newton’s first law says that the object would move in a stra ...

CENTER OF MASS The center of mass is the point where all of the mass of an object can be considered to be concentrated; it’s the ...

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In the example above, xcm = = = −8. The system behaves as if an object with mass 8 kg were 8 units to the left of the origin. If ...

Here’s How to Crack It The center of mass of the bar alone is at its midpoint (because it is uniform), so we can treat the total ...

We figure out the x- and y-coordinates of the center of mass separately. ...

Therefore, the center of mass is at (xcm, ycm) = (1.5, −5) relative to the midpoint of the bar. Questions 7-8 A man of mass 70 k ...

When the man reaches the other end of the barge, the center of mass will, by symmetry, be 11.25 meters to the right of the midpo ...

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ROTATION AND TRANSLATION All motion is some combination of translation and rotation, which are illustrated in the figures below. ...

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ROTATIONAL DYNAMICS The dynamics of translational motion involve describing the acceleration of an object in terms of its mass ( ...

TORQUE We can tie a ball to a string and make it undergo circular motion, but how would we make that ball itself spin? We could ...

In which situation will I close the soor faster? Situation 1 allows you to close the door with a greater speed. Force isn’t the ...