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    North and south celestial poles

    Homework Statement The earth's angular momentum is directed toward which celestial pole(north or south)? Homework Equations none The Attempt at a Solution I just assume that it is the south celestial pole considering that the earth is spinning from left to right, or west to east...
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    Help with wording and work

    Homework Statement Energy is conventionally measured in Calories as well as in joules. One Calorie in nutrition is one kilocalorie, defined as 1 kcal = 4186 J. Metabolizing 1 g of fat can release 9.00 kcal. A student decides to try to lose weight by exercising. She plans to run up and down...
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    Movable pulleys and force

    1. Homework Statement In the figure below, the man and the platform together weigh 780 N. The pulley can be modeled as frictionless. Determine how hard the man has to pull on the rope to lift himself steadily upward above the ground. ____________N 2. Homework Equations...
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    Simple problem that webassign keeps saying wrong

    1. Homework Statement The average speed of a nitrogen molecule in air is about 670 m/s, and its mass is about (4.68 x 10^-26)kg. (a) If it takes (3.60 x 10^-13)s for a nitrogen molecule to hit a wall and rebound with the same speed but moving in an opposite direction (assumed to be the...
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    Calculate angles from axis with a 3d vector

    Homework Statement A vector is given by R(vector) = 1.90 ihat + 1.30 jhat + 2.92 khat. Find the magnitude of the vector Find the angle between the vector and the x, y, and z axis Homework Equations I have read something about dot product but im not sure if it applies here The Attempt at...
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    WEBASSIGN DUE at 12:00 in the afternoon today HELP

    Homework Statement I have a problem that is urgent and due at 12 afternoon today. I will give you the problem and i dont know if you will get it or not in time. It deals with uncertainties in mass and volume to create a specific density with a new uncertainty. Here is the problem: The...