CLICKER QUESTION FOR EXAM 41. Assume the moons orbit is circular, the mass of the earth is 6 x 10^24 kg, the mass of the moon is 7x10^22 kg and the orbital radius is 4x10^9m.

a. What is the moons kinetic energy in J ?G(21/4) x 10^37

b. What is the moons total energy in J ?

-G(21/4) x 10^37

2. The earths perihelion and aphelion distances are 1.47 x 10^8 km and 1.52 x 10^8 km, respectively. If the speed of the earth at perihelion is 30.3 km/s, what is the speed at aphelion, km/s?= 29.3

3. Four masses are placed at each of the 4 corners of a square. The square edge length is d. The masses on each of 2 left corners are 2 kg. The masses on each of the right corners are 1 kg. a. If a mass is placed at the center of square, what is the magnitude of acceleration in m/s^2?= (2 G)/d^2

b. If the mass at the center of square has mass M how much kinetic energy must it has to escape the orbit of the other 4 masses in J ?= (6GM)/d

4. Consider a mini planet orbiting around a heavy but very small sun of mass M. the planet mass is 2kg. at t = 0, the mini planet is 1 m from sun. For each of the following instantaneous orbiting speed at t= 0, if the orbit is elliptical and non circular.0 < V < V circular ellipsesV = V circular circleV circular < V < V escape elliptical V escape < V unbound

5. Two identical satellites orbit the earth. The orbits are circular and the radius of orbit for satellite 2 is twice the radius for satellite 1 , R = 2R. what is false ?A. K2 = K1B. U2 = U1C. E2 < E1D. UI/E1 = U2/E2

6. A mass of 250 kg rests on square piston on top of a tank filled with liquid. The edge of the piston is 0.5m, the depth of tank is 2m. (volume density of liquid is 1000 kg/m3 , g = 10m/s2)a. Pressure at the top of the tank , just below the piston, in N/m2?10,000

b. Pressure at the bottom of the tank , in N/m2?30,000

7. Consider a rectangular tank, full of a liquid of density 600kg/m3. The tank depth is 8m. the 1st piston has area of 2x10^-3 m2, and the 2nd piston has area of 4x10^-3 m2.a. If there is no downward force on the pistons, the pressure at the bottom is ?50,000N/m2

b. If the piston of smaller area supports a mass of 10kg, and the piston of the larger area supports a 2nd mass such that it is held in place, mass of the 2nd mass is?20 kg.

c. If the piston of smaller area supports a mass of 10kg, and the larger area of piston supports a second mass such that it is held in place, pressure at the bottom is ?50,000N/m2

8. A Utube is filled with a fluid of density 600kg/m3 has a cross sectional area of 2 m2. The left side of tube rises 3m from bottom and the right side rises to 2m. what is the downward force to keep the piston capping at the right side secure ?12, 000 N

9. A cube is filled with liquid density 800kg/m3. The cube edge length is 0.02m. a. Force on the bottom surface of cube ?0.06

b. Force on the side of the cube ?0.03

10. A cylinder of radius 0.5 m and a mass of 400 kg float on the surface of a fluid of density 1200kg/m3. How far below the surface will cylinders edge sink before reaching equilibrium in m?0.42

11. A cube of wood, of edge length L floats in water with its bottom surface parallel to the water level. The mass density by volume of wood is the density of water. At equilibrium, what is the distance between bottom of cube and the original water level?

L/4

12. Consider a mass spring system in harmonic oscillation. The amplitude of displacement oscillation is Xm, and the frequency of oscillation is w. which is false ?A. If x(t1) = -Xm, then v(t1) = 0B. If v(t2) = - wXm, then x(t2) = XmC. If a(t3) = -w^2Xm, then x(t3) = XmD. If a(t4)= w^2Xm, then x(t4)= - Xm

13. A particle moves back and forth along x axis from x = -Xm to x = Xm, in simple harmonic motion with period T. At time t =0, it is at x =Xm, when t = 0.75T;It is at x = 0 and is travelling toward x =Xm

14. The displacement of an object oscillating on a spring is given by x(t) = Xm cos(wt +). If the initial displacement is 0 and initial velocity is in ve x direction , then the phase constant , , is ?/2 rad

15. An object of mass M oscillating on the end of a spring with spring constant K has amplitude A. its maximum speed is

16. A mass of 1 kg is attached to a spring of spring constant 39.4N/m . at t =0, the oscillator is at equilibrium and its velocity is -6.28m/s. a. Max displacement amplitude ?1

b. Max acceleration amplitude ?39.4

c. Max velocity amplitude ?6.3

d. How much time elapses before the position is at its max +ve displacement ?0.75

e. How much time elapses before the velocity is at its max +ve value ?0.5

17. A mass of 1 kg is in equilibrium on a frictionless surface making a 45 degree angle with the x axis. It is connected to a spring constant of 1 N/m. from its equilibrium point, you pull the mass downward along the incline 0.1 m and release it from rest. How long it will take the mass to reach the top of its trajectory. 3.1

18. A cylinder of radius of 0.5 m and a mass of 400 kg, floats on the surface of a fluid of density 1200kg/m3. If the cylinder is shoved downward and released, what will be its oscillation frequency in rad/s?4.9