You are using a rotary encoder to determine the distance a robot has traveled. the rotary encoder is directly connected to one of the wheels that has a diameter of 10cm. assume the encoder has 16 lines/revolution and that both the rising and falling edges (2x mode) are detected. what is the smallest detectable change of the rover traveling distance? if you want the rover to travel 2 meters before making a turn, how many encoder counts (rise and fall) are needed before sending a turn command? if you want to upgrade the encoder so that the smallest detectable distance change is ±0.20cm, what would be the required lines/revolution?

work is a product of force and displacement. the choice with displacement but in a different direction is not right as force not acting along the displacement will not generate work.

so the answer is force in the same direction as the displacement vector and the motion.

steps in the scientific method

step 1: ask a question. for the first step, your child form a question, hopefully one that can be answered!

step 2: do background research.

step 3: construct a hypothesis.

step 4: test your hypothesis by doing an experiment.

step 5: analyze the data and draw a conclusion.

step 6: share your results.

answer:     d

when the compass placed near the working of electric wire, the compass needle will be redirected towards the magnetic field created by wire.

the electric wire cause the magnetic field just like a magnet causes magnetic field.

the electric currents always produces their magnetic fields. when we put the compass near the electric wire the current passes through it, and the needle of the compass will not move in north or south, instead, the needle will be pointed in the direction of   magnetic field created by the wire.