hai otoo cùng chuyển động đều trên dường thẳng nếu 2 ô tô đi ngược chiều thì cứ 20p khoảng cách của chúng giảm đi 30km nếu chúng đi cùng chiều thì cứ 10p khoảng cách của chúng giảm đi 10km. tính vận tốc mỗi xe

Samir watches a 100-minute movie on his spaceship. maria's spaceshipe flies in the same direction as samir's spaceship but she observes his move to last 125 minutes and his spaceship to be 40 m long. how long does samir observe his own spaceship to be? according to an observer on earth, planet x is stationary. maria and samir depart earth on their spaceships at the same time, each flying at 0.5c. maria flies toward planet x and samir flies in the opposite direction. according to maria, her voyage to planet x takes 9 years. how many years does marias voyage take according to samir?

The diagram shows a boulder rolling down a hill into a valley and then up the opposite hill. at which position does the boulder have the greatest kinetic energy? ab c d

What happens during the fall in september