Answer:
7.28×10⁻⁵ T
Explanation:
Applying,
F = BILsin∅............. Equation 1
Where F = magnetic force, B = earth's magnetic field, I = current flowing through the wire, L = Length of the wire, ∅ = angle between the field and the wire.
make B the subject of the equation
B = F/ILsin∅.................. Equation 2
From the question,
Given: F = 0.16 N, I = 68 A, L = 34 m, ∅ = 72°
Substitute these values into equation 2
B = 0.16/(68×34×sin72°)
B = 0.16/(68×34×0.95)
B = 0.16/2196.4
B = 7.28×10⁻⁵ T
Answer:
d)energy
Explanation:
Waves can transfer energy over distance without moving matter the entire distance. For example, an ocean wave can travel many kilometers without the water itself moving many kilometers. The water moves up and down—a motion known as a disturbance. It is the disturbance that travels in a wave, transferring energy.
Answer:
![\displaystyle X_T=66.6\ km](https://tex.z-dn.net/?f=%5Cdisplaystyle%20X_T%3D66.6%5C%20km)
Explanation:
<u>Accelerated Motion
</u>
When a body changes its speed at a constant rate, i.e. same changes take same times, then it has a constant acceleration. The acceleration can be positive or negative. In the first case, the speed increases, and in the second time, the speed lowers until it eventually stops. The equation for the speed vf at any time t is given by
![\displaystyle V_f=V_o+a\ t](https://tex.z-dn.net/?f=%5Cdisplaystyle%20V_f%3DV_o%2Ba%5C%20t)
where a is the acceleration, and vo is the initial speed
.
The train has two different types of motion. It first starts from rest and has a constant acceleration of
for 182 seconds. Then it brakes with a constant acceleration of
until it comes to a stop. We need to find the total distance traveled.
The equation for the distance is
![\displaystyle X=V_o\ t+\frac{a\ t^2}{2}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20X%3DV_o%5C%20t%2B%5Cfrac%7Ba%5C%20t%5E2%7D%7B2%7D)
Our data is
![\displaystyle V_o=0,a=0.987m/s^2,\ t=182\ sec](https://tex.z-dn.net/?f=%5Cdisplaystyle%20V_o%3D0%2Ca%3D0.987m%2Fs%5E2%2C%5C%20t%3D182%5C%20sec)
Let's compute the first distance X1
![\displaystyle X_1=0+\frac{0.987\times 182^2}{2}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20X_1%3D0%2B%5Cfrac%7B0.987%5Ctimes%20182%5E2%7D%7B2%7D)
![\displaystyle X_1=16,346.7\ m](https://tex.z-dn.net/?f=%5Cdisplaystyle%20X_1%3D16%2C346.7%5C%20m)
Now, we find the speed at the end of the first period of time
![\displaystyle V_{f1}=0+0.987\times 182](https://tex.z-dn.net/?f=%5Cdisplaystyle%20V_%7Bf1%7D%3D0%2B0.987%5Ctimes%20182)
![\displaystyle V_{f1}=179.6\ m/s](https://tex.z-dn.net/?f=%5Cdisplaystyle%20V_%7Bf1%7D%3D179.6%5C%20m%2Fs)
That is the speed the train is at the moment it starts to brake. We need to compute the time needed to stop the train, that is, to make vf=0
![\displaystyle V_o=179.6,a=-0.321\ m/s^2\ ,V_f=0](https://tex.z-dn.net/?f=%5Cdisplaystyle%20V_o%3D179.6%2Ca%3D-0.321%5C%20m%2Fs%5E2%5C%20%2CV_f%3D0)
![\displaystyle t=\frac{v_f-v_o}{a}=\frac{0-179.6}{-0.321}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20t%3D%5Cfrac%7Bv_f-v_o%7D%7Ba%7D%3D%5Cfrac%7B0-179.6%7D%7B-0.321%7D)
![\displaystyle t=559.5\ sec](https://tex.z-dn.net/?f=%5Cdisplaystyle%20t%3D559.5%5C%20sec)
Computing the second distance
![\displaystyle X_2=179.6\times559.5\ \frac{-0.321\times 559.5^2}{2}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20X_2%3D179.6%5Ctimes559.5%5C%20%5Cfrac%7B-0.321%5Ctimes%20559.5%5E2%7D%7B2%7D)
![\displaystyle X_2=50,243.2\ m](https://tex.z-dn.net/?f=%5Cdisplaystyle%20X_2%3D50%2C243.2%5C%20m)
The total distance is
![\displaystyle X_t=x_1+x_2=16,346.7+50,243.2](https://tex.z-dn.net/?f=%5Cdisplaystyle%20X_t%3Dx_1%2Bx_2%3D16%2C346.7%2B50%2C243.2)
![\displaystyle X_t=66,589.9\ m](https://tex.z-dn.net/?f=%5Cdisplaystyle%20X_t%3D66%2C589.9%5C%20m)
![\displaystyle \boxed{X_T=66.6\ km}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cboxed%7BX_T%3D66.6%5C%20km%7D)
Answer:
There's one or two reasons, depending on what is meant by "wind-powered car".
The first reason is that it's impossible for any transfer of energy to be 100% efficient. There will always be frictional losses.
Secondly, if the company means that they want to attach a wind turbine to the car so that the car is powered by the same wind that it generates, that violates the conservation of energy.
Answer: An iron atom emits particles when it is struck by light (by the photoelectric effect)
Explanation:
The first atomic model was the one proposed by Jhon Dalton, according to which it is postulated that:
"Matter is made up of indivisible, indestructible and extremely small particles called atoms."
That is, <u>the atom is a solid and indivisible mass.
</u>
However, the fenomenom by which an iron atom emits particles when it is struck by light (known as the photoelectric effect) can not be explaind by this<u> indivisible atom</u> model.
To understand it better:
The <u>photoelectric effect</u> consists of the emission of electrons (electric current) that occurs when light falls on a metal surface under certain conditions.
This is possible by considering light as a stream of photons, where each of them has energy. <u>This energy is be able to pull an electron out of the crystalline lattice of the metal and communicate, in addition, a kinetic energy. </u>This means the atom is not indivisible, but it is a composition of different particles.
In fact, currently it is known that each atom is composed of a nucleus and one or more electrons attached to the nucleus, which is composed of one or more protons and typically a similar number of neutrons.