Two hikers start from the top of the same hill but take different paths to the bottom. Hiker A weighs more than hiker B. The hikers take the paths shown in the figure. Hiker B takes a long time to descend than hiker A. Which of the following is a correct statement about the change in gravitational potential energy ΔUA for the Earth-hiker A system and the change in gravitational potential energy ΔUB for the Earth-hiker B system? ΔUA=ΔUB, because the height descended for both is the same. ΔUA⁢=ΔUB, because the height descended for both is the same. A ΔUA ΔUB, because the time required for hiker A to descend the hill is shorter. ΔUA⁢>ΔUB, because the time required for hiker A to descend the hill is shorter. D ΔUA>ΔUB, because the gravitational force exerted on hiker A is greater.

First, launch the video below. you will be asked to use your knowledge of physics to predict the outcome of an experiment. then, close the video window and answer the question at right. you can watch the video again at any point. part a as in the video, we apply a charge +q to the half-shell that carries the electroscope. this time, we also apply a charge –q to the other half-shell. when we bring the two halves together, we observe that the electroscope discharges, just as in the video. what does the electroscope needle do when you separate the two half-shells again? view available hint(s) as in the video, we apply a charge + to the half-shell that carries the electroscope. this time, we also apply a charge – to the other half-shell. when we bring the two halves together, we observe that the electroscope discharges, just as in the video. what does the electroscope needle do when you separate the two half-shells again? it deflects more than it did at the end of the video. it deflects the same amount as at end of the video. it does not deflect at all. it deflects less than it did at the end of the video. submit

Which of the following changes will result in a stronger electromagnet? a. using fewer coils of wire b. using a higher voltage c. using a shorter nail d. using a longer wire

An automobile steering wheel is shown. what is the ideal mechanical advantage? if the ama is 8, what is the efficiency of the steering wheel?