Recent content by yoyo16

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    Calculus - How to minimize x^2 + (1/x^2)

    Oh ok so since it is absolute it would be 1 right?
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    Calculus - How to minimize x^2 + (1/x^2)

    Is it possible for the minimum to be a smaller value or would the smallest value be 1?
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    Calculus - How to minimize x^2 + (1/x^2)

    Homework Statement Find a positive number such that the sum of the square of the number and its reciprocal is a minimum. Homework Equations The Attempt at a Solution y=X^2+(1/X^2) Derivative=2x-2x^(-3) 0=2x-2x^3 2/x^3=2x 2=2x^4 1=x^4 x=1 The answer I got was 1 but I'm...
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    Coefficient of kinetic friction forces

    So how would you find out the friction force without knowing the normal force?
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    Coefficient of kinetic friction forces

    Homework Statement Find the applied force for a object if the coefficient of kinetic friction equals 0.30 and the acceleration equals 5m/s^2. The applied force makes a 40 degree angle with the horizontal. The mass of the object is 10kg. Homework Equations Fnet=ma The Attempt at a...
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    Kinematics Question -- 2 Runners Racing Each Other

    Homework Statement Dave and Andrew are racing. Dave running at a constant speed of 20m/s is passed by Andrew. 2.0s after Andrew passes, Dave accelerates at 1.0m/s^2 until he catches up with Andrew 25s later. What is Andrew's velocity (he does not accelerate)? Homework Equations...
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    Projectile Motion Ball Hurl Question

    Oh ok, I got the answer. Thanks so much !
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    Projectile Motion Ball Hurl Question

    The angle must be 45 degrees to get max range right?
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    Projectile Motion Ball Hurl Question

    Homework Statement If you can hurl a ball so that its initial speed is 30m/s, what is the widest river you can throw it across? Homework Equations The range equations, t=2(vi)(sintheta)/g d=visin2theta/g The Attempt at a Solution I know you have to use components so what I...
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    Projectile Motion Jump Question

    Thanks guys for the help!
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    Projectile Motion Jump Question

    I'm sorry about that. 8.9m was for the horizontal distance.
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    Projectile Motion Jump Question

    Homework Statement A person jumps 8.9m. The person's takeoff speed was 15m/s. What is the angle relative to the ground at takeoff? Homework Equations The Attempt at a Solution I found t using the kinematic formula to be 0.5s using the formula. d=vit+1/2at^2. Can someone tell...
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    Does Air Resistance Cause a Ball to Take Longer Falling Down Than Rising Up?

    Yes. How would you use that when explaining the answer for this question?
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    Does Air Resistance Cause a Ball to Take Longer Falling Down Than Rising Up?

    Homework Statement If a ball is thrown upwards and lands in the same spot, would it take longer to reach max height or drop back down from the max height? Also use air resistance. Homework Equations The Attempt at a Solution I believe that it would take longer for the object to...
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    Understanding Vector Addition and Magnitude Equality

    I think that A and B would add up to make the resultant vector C. That means A and B would be perpendicular to each other.