물리학 1 연습문제 풀이

3-51 (Halliday 9 th ed.)

4-86 (Halliday 9 th ed.)

5-54 (Halliday 9 th ed.) Figure shows four penguins that are being playfully pulled along very slippery (frictionless) ice by a curator. The masses of three penguins and the tension in two of the cords are m 1 =12 kg, m 3 =15 kg, m 4 =20 kg, T 2 =111 N, and T 4 =222 N. Find the penguin mass m 2 that is not given.

5-66 (Halliday 9 th ed.)

6-34 (Halliday 9 th ed.)

6-49 (Halliday 9 th ed.) In figure, a car is driven at constant speed over a circular hill and then into a circular valley with the same radius. At the top of the hill, the normal force on the driver from the car seat is 0. The driver's mass is 70.0 kg. What is the magnitude of the normal force on the driver from the seat when the car passes through the bottom of the valley?

6-70 (Halliday 9 th ed.) Figure shows a conical pendulum, in which the bob (the small object at the lower end of the cord) moves in a horizontal circle at constant speed. (The cord sweeps out a cone as the bob rotates.) The bob has a mass of kg, the string has length L=0.90 m and negligible mass, and the bob follows a circular path of circumference 0.94 m. What are (a) the tension in the string and (b) the period of the motion?