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1. ### Hooke's Law: F= -k x. Why is there a negative in the equation?

...negative sign. For example, let x = 2 meters and k = 10 (m/N). Then the equation becomes... not stretched at all.) At this point k times x gives the magnitude of the restoring...

6 Answers · Science & Mathematics · 24/12/2008

2. ### Suppose the velocity v of a motorboat coasting in water satisfies the differential equation dv/dt = k*v^2.?

You have that: dv/dt = k*v^2 and you should already be able to tell that k is going to be a... that when v = 5 m/s, dv/dt = -1 m/s^2, so: -1 m/s^2 = k*(5 m/s)^2 k = -1/(25 m) The original differential equation is separable: v^(-2) dv...

1 Answers · Science & Mathematics · 20/10/2009

3. ### how do you determine the activation energy from temperature and k?

... about the Arrhenius equation as the model, correct? k = A0 * Exp( Ea / RT ) where k...) * (1/T) + ln A0 If we let y = ln k b = ln A0 m = Ea / R x = 1/T...

1 Answers · Science & Mathematics · 05/10/2009

4. ### spring- finding k and mass?

The period (T1) of a mass (m1) on a spring(k) is: T1 = 2 pi sqrt (m1/k) Solve for...proportional to the square of the period (instead of plugging in k and canceling). Anyway, they give you the...

1 Answers · Science & Mathematics · 26/02/2010

5. ### Another physics K**LER prob?

Use conservation of energy (K + U)1 = (K + U)2 K1 = 0 and U1 = 0 (Set...

1 Answers · Science & Mathematics · 05/03/2011

6. ### phisics problem:a drop with primary radius r0 falls from height and gets moisture from air dm/dt=ks?

... know that the drop gains mass according to: dM/dt = k*S = k*4*pi*r^2 Substitute the expression for the mass as a function...

2 Answers · Science & Mathematics · 28/06/2006

7. ### What are the dimentions of k?

1) k = Force/ displcement = NEwton / m = kg m /(s^2 m) = kg /s^2 so dimensional formula [ M^1 T^-2] 2) k= Force/ Velocity ^n = kg m s^n __________ (s^2)(m^n) = kg m...

2 Answers · Science & Mathematics · 11/01/2011

8. ### joules of K ENERGY WHEN 1 KG FAILS AT 6M/S?

K.E = 1/2mv^2 wher, m is mass = 1 kg v is velocity = 6m/s K.E = 1/2(1)(6)^2 K.E = 1/2(36) K.E = 18 joules

1 Answers · Science & Mathematics · 22/10/2012

9. ### Show that the function has a maximum at E = ((b*k*T)/2)^2/3?

Given: f(E)=e^(-(E/(k∗T))−(b/√E)) = {e^(-(E/(k∗T)))}{e^−(b/√E...)v(E) + u(E)v'(E) d{f(E)}/dE = {-(1/(k∗T)e^(-(E/(k∗T)))}{e^−(b/√E)} + {e^(-(E/(k...

1 Answers · Science & Mathematics · 12/02/2013

10. ### As Physics help: The Isotope potassium K (atomic number = 40 mass number = 19) can decay by positron emission?

"The Isotope potassium K (atomic number = 40 mass number = 19)"... new element (Z=18) is argon. So K-40 has turned in Ar-40. We...

2 Answers · Science & Mathematics · 18/12/2011