L'étoile Sirius est l'étoile la plus brillante lorsqu'on observe le ciel. Elle est située à environ 86 000 000 000 000 km de la Terre. 1) À combien d'années-lumière Sirius est-elle située de la Terre ? 2) Quelle durée la lumière de Sirius met-elle pour nous parvenir ?

You are driving directly behind a pickup truck, going at the same speed as the truck. a crate falls from the bed of the truck to the road. (a) will your car hit the crate before the crate hits the road if you neither brake nor swerve? (b) during the fall, is the horizontal speed of the crate more than, less than, or the same as that of the truck?

Ablock having mass m slides down an inclined plane. the force of friction between the block and the inclined plane is f, the block's weight is m g, and the normal force is n. (a) draw a free – body force diagram showing the forces acting on the block. (b) write down all relevant newton’s equations for a given situation.

Ais a multilevel way of grouping items based on common properties among them. a. memory b. conceptual hierarchy c. schema d. semantic network