Answer:
57 N
Explanation:
Force on a current carrying conductor in a magnetic field
B = 12 X 10⁻⁴ T
= Bil where B is magnetic field , i is current and l is length of conductor
force required = 12 x10⁻⁴ x 47500 x 1
= 57 N
Answer: D. it has been demonstrated to be without exception under certain stated conditions.
Explanation:
A <u>Law</u> is an affirmation (something established) based on repeated long-term observation of a phenomenon that has been studied and verified.
That is: A law is present in all known theories and therefore is considered universal. In addition, a law can not be refuted, nor changed, because its precepts have been proven through various studies.
<u>Unlike theory</u>, which is the set of rules and principles that describe and explain a particular phenomenon and <u>is subject to changes as new evidence emerges that gives meaning to it. </u>
Then, based on what is explained above, the law of universal gravitation is a statement that exists because it was rigorously tested and verified, therefore it can not be refuted.
Answer:
26.5 minutes
Explanation:
When the airplane is flying due West from Denver to Reno, the due-East wind with speed of 80km/h would reduce the ground speed by 80 km/h.
Its Denver to Reno ground speed is 900 - 80 = 720 km/h
The time it takes to cover 1200km at this speed is 1200 / 720 = 1.67 hours
On the other hand, when it returns from Reno to Denver in the due-East direction, the due-East wind with speed of 80km/h would add to the ground speed by 80 km/h
Its Reno to Denver ground speed is 900 + 80 = 980 km/h
The time it takes to cover 1200 km at this speed is 1200 / 980 = 1.22 hours
The difference it flight time would be 1.67 - 1.22 = 0.44 hours or 26.5 minutes
Explanation:
because the moon has less mass than earth, the force due to gravity at the lunar surface is only about 1/6 that on earthso,the weight of a body on earth is 6×5N =30N
Answer:
Explanation:
a rigid object in uniform rotation about a fixed axis does not satisfy both the condition of equilibrium .
First condition of equilibrium is that net force on the body should be zero.
or F net = 0
A body under uniform rotation is experiencing a centripetal force all the time so F net ≠ 0
So first condition of equilibrium is not satisfied.
Second condition is that , net torque acting on the body must be zero.
In case of a rigid object in uniform rotation , centripetal force is applied towards the centre ie towards the line joining the body under rotation with the axis .
F is along r
torque = r x F
= r F sinθ
θ = 0 degree
torque = 0
Hence 2nd condition is fulfilled.
