Physics: 1-11 Questions & Answers

Physics: 1-11 Questions & Answers "Centrifugal forces" are an apparent reality to observers in a reference frame that is ... A. At rest B. An intertial reference frame C. Moving at a constant velocity D. Rotating E. Bouncing - ANSWER: D. Rotating A 10-kg brick and a 1-kg book are dropped in a vacuum. the force of gravity on the 10kg brick is.. - ANSWER: 10 times as much as the force on the 1 kg book A 100-N lantern is suspended by a pair of ropes with 120 degrees between them (Each 60 degrees from the vertical). The tension in each rope is - ANSWER: 100N A 15-N force and a 45-N force act on an object in opposite directions. What is the net force on the object - ANSWER: 3oN A 2-kg ball is thrown at 3 m/s what is the balls momentum - ANSWER: 6 kg ms a 20 N falling object encounters a 4 N of air resistance. the magnitude of the net force on the object is - ANSWER: 16 N A 4 kg ball has a momenutim of 20 kg ms what is the balls speed - ANSWER: 5 ms A 5-N force and a 30-N force act in the same direction on an object. What is the net force on the object ? - ANSWER: 35N A 6 N falling object encounters a 6 N of air resistance. the magnitude of the net force on the object is - ANSWER: 0 N A 60-kg person on in-line skates pushes against a wall with a force of 30 N and recoils. What acceleration does that person experience? - ANSWER: 0.5 m/s/s A 60-N object moves at 1 m/s. Its kinetic energy is - ANSWER: b. 30 J A bag of sports equipment has a mass of 10.0 kilograms and a weight of - ANSWER: 98 N A ball is moving at 6 ms and has a momentum of 24 kg ms what is the balls mass - ANSWER: 4 kg A ball is thrown into the air at some angle. At the very top of the ball's path, its velocity is - ANSWER: D. entirely horizontal A ball is thrown into the air with 100 J of kinetic energy which is transformed to gravitational potential energy at the top of its trajectory. When it returns to its original level after encountering air resistance, its kinetic energy is - ANSWER: c. less than 100 J A ball is thrown straight up. At the top of its path its acceleration is - ANSWER: about 10 m/s squared A ball is thrown straight up. At the top of its path its instantaneous speed is - ANSWER: 0 m/s A ball is thrown straight upward a 10 m/s. Ideally (no air resistance), the ball will return to the thrower's hand with a speed of - ANSWER: C. 10 m/s