I think it is D. I hope this helps
Distance, Force
<u>Explanation:</u>
1) Increasing the load will add to the friction on the bearings of the pulleys, thus reducing the efficiency of the system. The ideal mechanical advantage won't change since the ideal mechanical advantage ignores friction.
2) Increasing the number of pulleys will increase the ideal mechanical advantage, but because of friction it will decrease the efficiency. The more pulleys that are turning, the more friction there is, and the less efficient the system will be.
3) Work = force x distance, and what machines do is alter the amount of force you can apply while at the same time reducing the distance moved by the same factor. For instance, a jack multiplies the force you apply by a factor of 100, when you push down on the handle of the jack 100 cm, the car will only go up 1 cm. So the force x distance is the same 100 x force x 1/100 x distance.
Answer:
<h2>Non-Ionizing Radiation From Wireless Technology
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Radiofrequency (RF) energy is a type of electromagnetic radiation. It is used to transmit signals carrying information in the form of radio waves. Radio waves are broadcast using a transmitter. When the radio waves reach a receiver, the signal is converted back into the information that was originally sent by the transmitter. When you talk on a cell phone, your cell phone acts as a transmitter and your voice is carried on radio waves to the person you are calling. Their phone acts as the receiver and converts the signal back into your voice. In addition to cell phones, other wireless devices such as radios, Wi-Fi routers, satellites, radars and pacemakers can send or receive RF energy waves.
Answer:
a reference point allows you to determine the motion of an object :)
example: when your in a car and u look out the window and your moving fast than the car next to you. It seems that way because the car next to you is actually moving much slower.