<span>If the swimmer is swimming perpendicular to the current, it will take her 66m / 0.42 m/s = 157.14 seconds to cross the river. At the same time, the current will be taking her downstream at a rate of 0.32 m/s. So, when she reaches the opposite bank, her total downstream distance traveled will have been 0.32*157.14 = 50.28 meters.</span>
It does produce 'sound' ... a compression wave traveling through the air. But your ears don't hear a sound that's vibrating less than 20 or 30 times every second. If you could swing your pendulum that fast, you could hear the sound of its vibrations pushing the air around.
•Every action has an equal and opposite reaction (the object is putting force on the target, and the target is putting an equal amount of force back)
•Am object in motion (the object) will stay in motion unless an outside force acts upon it (the Target)
And as for the third one I really don’t know, those seem to be the only two, I’m sorry. I did what a could, Hope it kinda helps :)
Electrons that are further away from the nucleus have more energy. As they enter an "excited" state, they jump up orbits.
