Recent content by robvba

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    Block on incline with vertical force

    m*g*cos()?
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    Block on incline with vertical force

    It points down. The applied points up.
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    Block on incline with vertical force

    m*g*sin()
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    Block on incline with vertical force

    The figure shows a block on a 37 degree incline with a vertical arrow moving from the block upward (representing the applied force)
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    Block on incline with vertical force

    Homework Statement 3.0-kg block slides on a frictionless 37° incline plane. A vertical force of 15 N is applied to the block. The acceleration of the block is? Homework Equations m*g*sin() The Attempt at a Solution 3*9.8*sin(37) - 15 = 2.7
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    What is the net force on the roof

    yes i am :)
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    What is the net force on the roof

    Homework Statement If wind blows at 35 m/s over a house, what is the net force on the roof if its area is 240 m2 and is flat? Homework Equations Pat + 1/2 * pair * v^2 The Attempt at a Solution wind velocity - v - 35 area of roof - A - 240 density of air - p - 1.29 atmospheric...
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    Calculating Pressure Increase in Arteries with Fatty Tissue Build-Up

    Homework Statement Suppose that the build-up of fatty tissue on the wall of an artery decreased the radius by 10%. By how much would the pressure provided by the heart have to be increased to maintain a constant blood flow? Homework Equations Poiseuille's equation The Attempt at a...
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    What is the Centripetal Acceleration of a Car on a Circular Curve?

    Homework Statement A car is negotiating a flat circular curve of radius 50 m with a speed of 20 m/s. The maximum centripetal force (provided by static friction) is 1.2 × 104 N. What is the centripetal acceleration of the car? Homework Equations MAc = MV^2/R The Attempt at a...
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    Two objects collide and bounce off each other. Linear momentum

    Two objects collide and bounce off each other. Linear momentum A. is conserved only if the environment is frictionless B. definitely not conserved C. definitely is conserved D. is conserved only if the collusion is elastic A perfectly elastic collision is defined as one in which...
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    How Does Adding Mass Affect Spring Potential Energy?

    why do we assume that the string's displacement will double?
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    Where does gravitation of earth and sun cancel

    gravity experienced due to Earth on the sun = gravity experienced due to sun on the earth...?
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    Where does gravitation of earth and sun cancel

    I figure that F has to equal 0 and that one equation has to equal another.
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    Where does gravitation of earth and sun cancel

    Homework Statement For a spacecraft going from the Earth toward the Sun, at what distance from the Earth will the gravitational forces due to the Sun and the Earth cancel? Earth's mass: Me the Sun's mass: Ms Earth-Sun distance: r Homework Equations F=Gm1m2/r^2 The Attempt...
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    Calculating Contact Forces Between Three Blocks on a Frictionless Surface

    right. i meant Fba = - Fab (Force of A on B = negative Force of B on A)...?