Answer:
v = R w
With this expression we see that for each point at different radius the tangential velocity is different
Explanation:
They indicate that the angular velocity is constant, that is
w = dθ / dt
Where θ is the radius swept angle and t the time taken.
The tangential velocity is linear or
v = dx / dt
Where x is the distance traveled in time (t)
In the definition of radians
θ = s / R
Where s is the arc traveled and R the radius vector from the pivot point, if the angle is small the arc (s) and the length (x) are almost equal
θ = x / R
We substitute in the speed equation
v = d (θ R) / dt
The radius is a constant for each point
v = R dθ / dt
v = R w
With this expression we see that for each point at different radius the tangential velocity is different
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Answer:
The focal lenth (F) =+10.0cm
Explanation:
The formular for combined focal length (F) is given as;

In this question,
F1 = 20cm
F2 = -30cm
Plugging the values into the formuar above,

![1/f = 0.05 - 0.033[tex]1/f = -0.017f = [tex]1/ -0.017](https://tex.z-dn.net/?f=1%2Ff%20%3D%200.05%20-%200.033%3C%2Fp%3E%3Cp%3E%5Btex%5D1%2Ff%20%3D%20-0.017%3C%2Fp%3E%3Cp%3Ef%20%3D%20%5Btex%5D1%2F%20-0.017)
f = 58.82cm
i.e. the combination behaves as a converging lens (because of the postive sign) of focal length 58.82cm .
Answer:
Explanation:
Both these questions are based on the Universal Law of Gravitation, which is given by :
F = Gm1m2 / r²
2) F = 6.67 x 10⁻¹¹ x 8 x 10³ x 1.5 x 10³ / 1.5 x 1.5
F = 6.67 x 10⁻⁵ x 8 / 1.5
F = 35.57 x 10⁻⁵ N
3) F = 6.67 x 10⁻¹¹ x 7.5 x 10⁵ x 9.2 x 10⁷ / 7.29 x 10⁴
F = 6.67 x 10⁻³ x 7.5 x 9.2 / 7.29
F = 63.13 x 10⁻³ N