Bonsoir tout le monde j aurais besoin d'aide Lors d'un contrôle technique, on étudie le freinage d'une voiture de poids P= 9,6 kN. La force de freinage totale (avant et arrière) mesurée vaut F= 8,92 kN. 1. Quelles sont les forces qui s'appliquent sur la voiture ? Les schématiser à l'échelle. 2. Donner les caractéristiques de la résultante des forces. 3. Calculer la variation de vitesse de la voiture en 1 seconde lors du freinage en m·s-1 puis en km·h-1.

Athin, square metal plate measures 14 cm on each side and has emissivity of 0.60. the plate is heated to a temperature of 745°c. what is the rate at which the plate radiates energy ? the stefan-boltzmann constant is 5.67 × 10-8 w/(m2 ? k4). remember that the plate will radiate energy from both its top and bottom surfaces.

Suppose that two tanks, 1 and 2, each with a large opening at the top, contain different liquids. a small hole is made in the side of each tank at the same depth 1.57 m below the liquid surface, but the hole in tank 2 has 2.49 times the cross-sectional area of the hole in tank 1. (a) what is the ratio ρ1/ρ2 of the densities of the liquids if the mass flow rate is the same for the two holes? (b) what is the ratio rv1/rv2 of the volume flow rates from the two tanks? (c) at one instant, the liquid in tank 1 is 14.9 cm above the hole. if the tanks are to have equal volume flow rates, what height above the hole must the liquid in tank 2 be just then?

Use the right-hand rule for magnetic force to determine the charge on the moving particle. this is a charge.