Explanation:
voltage = current × resistance
5.
12 V = 4.2 A × resistance
resistance = 12 V / 4.2 A = 2.857142857... Ohm
FYI :
4.2 A would be a lot for a small electronic device like a CD player. that would be 12×4.2 = 50.4 Watt, and the CD player would get really hot.
6.
120 V = current × 12 Ohm
current = 120 V / 12 Ohm = 10 A
From a balistics pendulum as an example, which is probably where you are at...
Triangles, L = 12m, x_0 = 1.6, we need to find the angle (theta)
sin (theta) = 1.6/12 = 0.1333....
theta = ArcSin(0.1333...) = 0.1337 rad
Then, this is the height that the mass vertically raises in it's arc
y_2 = L-L*cos(theta) = 0.107 m
use y_2 in a kinematic swing...
<span><span>v=sqrt(<span><span>2g<span>y_2)</span></span></span>=1.45m/s</span></span>
Answer:
Maximum speed of the car is 17.37 m/s.
Explanation:
Given that,
Radius of the circular track, r = 79 m
The coefficient of friction, 
To find,
The maximum speed of car.
Solution,
Let v is the maximum speed of the car at which it can safely travel. It can be calculated by balancing the centripetal force and the gravitational force acting on it as :
v = 17.37 m/s
So, the maximum speed of the car is 17.37 m/s.
Answer:
Explanation:
The total force on the particle is given by
Then, by replacing we have:
![q\vec{v}\ X \vec{B}=q[7\hat{k}-9\hat{j}-\hat{k}]\\\\q\vec{E}=q[5\hat{i}-\hat{j}-2\hat{k}]\\\\\vec{F}=(9.61*10^{-19}C)[(7+9)\hat{i}+(-9-1)\hat{j}+(-1-2)\hat{k}]\\\\\vec{F}=(1.537*10^{-17}\hat{i}-9.61*10^{-19}\hat{j}-2.883*10^{-18}\hat{k})N](https://tex.z-dn.net/?f=q%5Cvec%7Bv%7D%5C%20X%20%5Cvec%7BB%7D%3Dq%5B7%5Chat%7Bk%7D-9%5Chat%7Bj%7D-%5Chat%7Bk%7D%5D%5C%5C%5C%5Cq%5Cvec%7BE%7D%3Dq%5B5%5Chat%7Bi%7D-%5Chat%7Bj%7D-2%5Chat%7Bk%7D%5D%5C%5C%5C%5C%5Cvec%7BF%7D%3D%289.61%2A10%5E%7B-19%7DC%29%5B%287%2B9%29%5Chat%7Bi%7D%2B%28-9-1%29%5Chat%7Bj%7D%2B%28-1-2%29%5Chat%7Bk%7D%5D%5C%5C%5C%5C%5Cvec%7BF%7D%3D%281.537%2A10%5E%7B-17%7D%5Chat%7Bi%7D-9.61%2A10%5E%7B-19%7D%5Chat%7Bj%7D-2.883%2A10%5E%7B-18%7D%5Chat%7Bk%7D%29N)
where the cross product can be made with the determinant method.
Hope this helps!!
Explanation:
For a charge concentrated nearly at a point, the electric field is directly proportional to the amount of charge; it is inversely proportional to the square of the distance radially away from the centre of the source charge and depends also upon the nature of the medium.
