Recent content by RobLikesBrunc

Yeah. I was wondering why the hell this got resurrected.

If you still can't even attempt the problem after what I've told you, you need to go back and actually learn the material. The displacement of the Canadian skier is given by: x = x_{0} + v_{i}t + \frac{1}{2}at^2. The displacement of the Norwegian skier is given by: x = x_{0} +...

Your intuition is right; notice how for the line charge, the sum actually depends on y (that's why the y has subscript i). And that makes sense--look at the problem, as you get farther and farther up the y-axis, the cosine of theta becomes smaller and smaller. So, even though the rod is...

I have no idea what d2 and d1 are. As for 2, you didn't really answer the question. The Canadian skier overtakes the Norwegian skier when they've gone the same distance. What equation describes the distance that the Canadian skier has gone in some time t? And what equation describes the...

To help you get started: 1. Write down the equation that describes the displacement (distance in this problem) of the Canadian skier and then the Norwegian skier. 2. What does it mean (think in terms of the above equations) for the Canadian skier to overtake the Norwegian skier? What condition...

Show us your attempt for each problem and where you're having trouble.

Because the time he used is a measure of how long it takes the floor to accelerate the woman in the opposite direction once she's impacted the form. It is the duration during which the floor is accelerating her (and, physically, it stems from the impact of the woman deforming the surface of the...

If you're unsure about how to plot a point in 3D space, I'm not too sure how I'm going to explain to you how to find the equation of a plane from three points. Open your calc 3 book and get to reading. The way I would do it is find a normal vector for the plane by taking a cross product of...

Correct (you have a rounding error, the velocity rounded should be 5.5 m/s--should get you closer to 3.8 * 10^(4) N).

Okay, I see the confusion. The question is poorly worded and assumes familiarity with the type of problem it's asking. It's really saying "The woman's body comes to rest within 8.00 * 10^-3 seconds after contacting the floor". So, the floor is accelerating her up for 8.00 * 10^-3 seconds...

8.00 * 10^-3 seconds is not the time that she drops for--it's the time period of her collision with the ground (i.e. the time period where the force from ground is still accelerating her up). So her final velocity has nothing to do with 8.00 * 10^-3 seconds.

The key is that the worker is pushing the block at constant speed, so acceleration (and therefore net force) must be zero. So, for the horizontal components we have: Fw cos(22) - Fn(0.40) = 0 where Fw is the force from the worker and Fn the normal force on the block. For the vertical...

Look at this carefully and tell me what you did wrong. Don't blindly use equations; think!

In Cartesian coordinates (-2,3,5) is the same thing as saying "-2 in the x-direction, 3 in the y-direction, and 5 in the z-direction". As movement in the x,y,z-directions don't affect the other directions, so yeah...although note that if you're moving on the y-axis, you're not only not moving on...

Also, are you sure that the answer is 300 N?