Answer:
Water stay in the bucket if the bucket is spin upside down and fast because due to centripetal force.
Explanation:
When the bucket is at highest point in the circular motion then there will be three forces work centripetal force in upward direction ann normal and weight will work in downward direction.
By newton law,
centripetal force=weight + normal force.
![\frac{mv^{2} }{r}=N+mg\\ N=\frac{mv^{2} }{r}-mg](https://tex.z-dn.net/?f=%5Cfrac%7Bmv%5E%7B2%7D%20%7D%7Br%7D%3DN%2Bmg%5C%5C%20N%3D%5Cfrac%7Bmv%5E%7B2%7D%20%7D%7Br%7D-mg)
If the water will stay in the bucket in upside direction then there will be normal force is positive which means the centripetal force is greater than weight.
And to increase the centripetal force velocity should be greater because it depends on velocity.
The practical application of centripetal force are discussed below:
(a) Turning of the car on a banked road or in circular track.
(b) Revolution of the earth around the sun.
Answer:
![v_2=29.13\ m/s](https://tex.z-dn.net/?f=v_2%3D29.13%5C%20m%2Fs)
Explanation:
It is given that,
Dimension of the rectangular roof, (6.17 m × 5.92 m)
The maximum net outward force, ![F=2\times 10^4\ N](https://tex.z-dn.net/?f=F%3D2%5Ctimes%2010%5E4%5C%20N)
The density of air, ![\rho=1.29\ kg/m^3](https://tex.z-dn.net/?f=%5Crho%3D1.29%5C%20kg%2Fm%5E3)
The Bernoulli equation is used to find wind speed of this roof blow outward. It is given by :
![P_1+\dfrac{1}{2}\rho v_1^2=P_2+\dfrac{1}{2}\rho v_2^2](https://tex.z-dn.net/?f=P_1%2B%5Cdfrac%7B1%7D%7B2%7D%5Crho%20v_1%5E2%3DP_2%2B%5Cdfrac%7B1%7D%7B2%7D%5Crho%20v_2%5E2)
Here,
(since air inside the roof is not moving)
![v_2=\sqrt{\dfrac{2(P_1-P_2)}{\rho}}](https://tex.z-dn.net/?f=v_2%3D%5Csqrt%7B%5Cdfrac%7B2%28P_1-P_2%29%7D%7B%5Crho%7D%7D)
Since, ![F=(P_1-P_2)A](https://tex.z-dn.net/?f=F%3D%28P_1-P_2%29A)
![v_2=\sqrt{\dfrac{2F}{\rho A}}](https://tex.z-dn.net/?f=v_2%3D%5Csqrt%7B%5Cdfrac%7B2F%7D%7B%5Crho%20A%7D%7D)
![v_2=\sqrt{\dfrac{2\times 2\times 10^4}{1.29\times 6.17\times 5.92 }}](https://tex.z-dn.net/?f=v_2%3D%5Csqrt%7B%5Cdfrac%7B2%5Ctimes%202%5Ctimes%2010%5E4%7D%7B1.29%5Ctimes%206.17%5Ctimes%205.92%20%7D%7D)
![v_2=29.13\ m/s](https://tex.z-dn.net/?f=v_2%3D29.13%5C%20m%2Fs)
So, the wind speed of this roof blow outward is 29.13 m/s. Hence, this is the required solution.
Answer:
No, because she is hoping that people will vote for her.
Explanation:
Altruism is when you do something for others and have very little expectation of getting something in return. In this case, Janetta expected something in return from her friends. We may not also be sure of the sincerity of Janetta appreciating friendship. From the above definition of altruism, we conclude that Janetta's actions are not altruistic because she hoped that people will vote for her.
Answer:
The magnitude of charge on the particle is
.
Explanation:
Given that,
The magnitude of electric field, E = 215 N/C
The electrical potential energy of the charge decreases by,
as it moves.
We need to find the magnitude of the charge on the moving particle. The change in electric potential energy is given by :
.........(1)
The electric potential in terms of electric field is given by :
![\Delta V=-Ed\\\\\Delta V=-215\times 0.02=-4.3\ V](https://tex.z-dn.net/?f=%5CDelta%20V%3D-Ed%5C%5C%5C%5C%5CDelta%20V%3D-215%5Ctimes%200.02%3D-4.3%5C%20V)
Equation (1) becomes :
![q=\dfrac{-6.9\times 10^{-19}}{-4.3}\\\\q=1.6\times 10^{-19}\ C](https://tex.z-dn.net/?f=q%3D%5Cdfrac%7B-6.9%5Ctimes%2010%5E%7B-19%7D%7D%7B-4.3%7D%5C%5C%5C%5Cq%3D1.6%5Ctimes%2010%5E%7B-19%7D%5C%20C)
So, the magnitude of charge on the particle is
.
When the ruler is broughı near the inetal knob, it repels electrons in the metal. Electrons move away froni the ruler and down the metal rod. The knob now has a positive charge. The thin pieces of metal foil at the bottom of the metal rod now have a negative charge.