The "correct" answer is A. But that's not what it illustrates at all! The equal force is exerted on the planet, just as it is in cases C and D, but it's too small to measure. This is the kind of thing that really annoys me about standardized tests.

phi: ah.. well.. at least I guess right.. I didn't think any of these worked exactly right.
what I think is that the state of massachusetts is run by a bunch of loons..

Having grown up in a state with standardized testing and managed to get a reasonable education in a public school, I'm pretty much in favor of standardized tests.

The question is not which of these things is evidence of the law, but which of these best "illustrates" the law, which is clearly A. The question is designed to show logical thought, not familiarity with physics, and I think it does that reasonably well.

I don't think A illustrates the law any more than C or D. It does a good job of illustrating elastic collisions, though. Perhaps a better one is the crumpling of both cars in an auto accident.

choice A - newton's third
choice B - newton's first
choice C - momentum
choice D - crack

I hope they're not all like that

yeah, tests like this do suck

E: That vibration your get in your arms after you whack someone with a baseball bat

DING! Bill, does the gold star have to be for grammar?

This is an appallingly bad question. A basketball bouncing on the floor is actually the best example of any of these (because the Earth will bounce too,by the amount by which the basketball bounces times the mass of the basketball divided by the mass of the Earth) but it's a really, REALLY poor example even so. I suspect that we are intended to pick B, which, as the survey creator undoubtedly knows, is actually an illustration of a different Newtonian Law of Motion, the one concerning inertia. (Is that the First or Second?) The book continues to move in a straight line when the car turns.

I would be terribly concerned about this test on the basis of this question, but I suspect that the question was chosen for precisely that purpose, so I'll try to reserve judgment because I have not seen a representative sample of the questions.

I wouldn't use *any* of these as an illustration of the third law, but since c and d are illustrations of the same thing and therefore neither of them can be right, it's got to be a or b, and a sounds righter than b.
Still, I'm appalled.

I confess: I got it from the Boston Globe, which quoted two questions, each equally appalling. I have since gone to look at their source and this is the first question of 30 in what appears to be a complete list of multiple choice science questions. Of those 30 I would say that only three are this bad, although a few others reveal serious cultural assumptions on the part of the test authors.

Y'all are totally missing the point. This is not testing whether or not students know anything about physics. Tenth grade, competency. I'm not suggesting it's a great question, but y'all are criticizing it on the wrong basis.

Is this a sample of fourth, eighth, and tenth grade test question? Remember, that has a great deal to do with how well the question is. Don't expect a fourth grade question to be the caliber of a tenth. Likewise don't expect a tenth grade question to be accurate for college physics. Also, remember that in this particular question you are asked which of these four examples is best in illustrating this principle. You disregard the worst three and are left with the one that is best. Maybe they are all bad, but one of these four was definitely better than the others.

Worcester, at least, has always done these tests. I graduated high school in 1989 and I took them in fourth, eighth and tenth grades.

This is a 10th grade question. I expect lack of blatant scientific inaccuracy from all educational material, from texts to tests. This question leaves students with an incorrect impression about Newton's Laws which then must be corrected in the classroom. And since none of the answers have anything to do with Newton's Third Law, the only reasoning ability we're testing is the ability of students to psych out tests (see dpolicar's answer).

grmbrand: or with an axe!

I think this is a terrible question. All of these cases involve acceleration, in which case the statement "every force is accompanied by an equal and opposite force" is not technically correct. Therefore, none of the answers listed is right. I guess I would flunk the test (though I would probably second-guess the examiners and figure they meant answer "A" to be the "correct" one). Last time I checked, I had passed the physics course at M.I.T. that covers laws of motion, so I certainly ought to be able to mass the MCAS on that subject... An "F" for the test writers, I'm afraid.

There's exactly one answer there that fits but it seems like a pretty poor illustration of the law unless, for some reason, you want to also talk about non-inertial reference frames.

I see I picked the wrong answer. How embarrassing. If A is correct though, then C and D are equally correct as the earth will accelerate towards the car or pencil as they accelerate towards the Earth.

One question. Did everyone learn the proper answer in high school or college? I think the amount of additional discussion concerning the earth also bouncing from the force of the drop is a little beyond high school physics. Of course I'm probably wrong on this and will be told so by many people.

I learned this crap in ninth grade.

I don't think the tests are such a bad idea.