Look up pulleys problem through Khan academy and a video should pop up with a problem similar and you should be able to walk through it .
4.Use Ohm’s Law to determine the resistance in a circuit if the voltage is 12.0 volts and the current is 4.0 amps.
A. 8.0 ohms B. 48 ohms C. 3.0 ohms D. 12 ohms
Ohm's law is V=IR, or I=V/R, or R=V/I. (I= current, V= voltage, R= resistance.) Let's plug in our variables: V=12.0, I=4.0, R=? into the equation R=V/I. 12.0/4.0=3.0, so the resistance is 3.0 ohms.
chromatic aberration problem do refractor telescopes have that reflectors don't
<u>Explanation:</u>
Chromatic aberration is a phenom in which light rays crossing through a lens focus at various points, depending on their wavelength. Chromatic aberration is a dilemma in which lens or refracting, telescopes undergo from. The various image distances for the respective colors affect various image sizes for them.
This involves the creation of disturbing color fringes in the image. Chromatic aberration can be pretty well adjusted by the use of an achromatic doublet. Here, a positive biconvex lens is coupled with a negative lens placed backward with greater dispersion. Thus partly compensates for the chromatic aberration.
The centripetal force is provided by the friction between the tyres and the ground. That's why a car will slip on ice, because there is less friction.