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For some stupid reason, I'm stuck on these questions (some of them pretty basic) It's been a while since I've done physics. Any help would be greatly appreciated!
1. A satellite weighs 104 N at ground control. What best approximates the acceleration it experiences in orbit at an altitude of twice the earths radius?
A. 111 m/s2
B. 2.5 m/s2
C. 1.1 m/s2
D. 0 m/s2
2. The sun is approximately 150 million kilometers from the earth. A yearthe time for one revolution of the earth around the sunis roughly π × 107 seconds. Assuming a circular orbit, what best approximates the average acceleration of the earth due to the sun?
A. 6 × 106 m/s2
B. 6 × 103 m/s2
C. 6 × 102 m/s2
D. 4 × 1019 m/s2
3. A rectangular book weighing 20 N with sides of 10 cm and 20 cm is placed on a horizontal table. Using each of your hands, you exert forces of 10 N each in opposite directions at opposite corners, such that you are pushing parallel to the shorter side in each case. What net torque are you providing to the book?
A. 0 N-m
B. 0.5 N-m
C. 1 N-m
D. 2 N-m
4. A hammer head with a mass of 500 g moving at 4 m/s collides with a nail (m = 4 g) and comes to a stop in 0.002 seconds. What average force acts on the nail during that time?
A. 106 N
B. 103 N
C. 8 N
D. 8 ×103 N
5. A solid plastic cube with uniform density (side length = 0.5 m) of mass 100 kg is placed in a vat of fluid whose specific gravity is 1.2. What fraction of the cubes volume floats above the surface of the fluid?
A. 1/5
B. 1/3
C. 2/3
D. 4/5
6. An object with mass 30 kg and specific gravity 3.6 is placed in a fluid whose specific gravity is 1.2. Neglecting viscosity, which of the following is true?
A. The acceleration of the object is (1/3)g and its apparent weight is 100N
B. The acceleration of the object is (2/3)g and its apparent weight is 100N
C. The acceleration of the object is (1/3)g and its apparent weight is 200N
D. The acceleration of the object is (2/3)g and its apparent weight is 200N
7. A fluid of density ρ flows through a horizontal pipe with negligible viscosity. The flow is streamline with constant flow rate. The diameter of the pipe at Point 1 is d and the flow speed is v. If the diameter of the pipe at Point 2 is d/3, then the pressure at Point 2 is:
A. Less than the pressure at Point 1 by 4ρv
B. Less than the pressure at Point 1 by 40ρv
C. More than the pressure at Point 1 by 4ρv
D. More than the pressure at Point 1 by 40ρv
8. An ideal fluid flows through a pipe with radius R with flow speed v. If the pipe splits up into three separate paths, each with radius (R/2), what is the flow speed through each of the paths?
A. v/3
B. 2v/3
C. 4v/3
D. 4v
9. Traveling at an initial speed of 1.5 x 106 m/s, a proton enters a region of constant magnetic field of magnitude 1.5 T. If the protons initial velocity vector makes an angle of 30° with the magnetic field, compute the protons speed 4 s after entering the magnetic field.
A. 5.0 × 105 m/s
B. 7.5 × 105 m/s
C. 1.5 × 106 m/s
D. 3.0 × 106 m/s
10. Consider two adjacent transparent media. The speed of light through Medium 1 is v1, and the speed of light through Medium 2 is v2. If v1 < v2, then total internal reflection will occur at the interface between these media if a beam of light is
A. incident in Medium 1 and strikes the interface at an angle of incidence greater than arcsin(v1/v2)
B. incident in Medium 1 and strikes the interface at an angle of incidence greater than arcsin(v2/v1)
C. incident in Medium 2 and strikes the interface at an angle of incidence greater than arcsin(v1/v2)
D. incident in Medium 2 and strikes the interface at an angle of incidence greater than arcsin(v2/v1)
1. A satellite weighs 104 N at ground control. What best approximates the acceleration it experiences in orbit at an altitude of twice the earths radius?
A. 111 m/s2
B. 2.5 m/s2
C. 1.1 m/s2
D. 0 m/s2
2. The sun is approximately 150 million kilometers from the earth. A yearthe time for one revolution of the earth around the sunis roughly π × 107 seconds. Assuming a circular orbit, what best approximates the average acceleration of the earth due to the sun?
A. 6 × 106 m/s2
B. 6 × 103 m/s2
C. 6 × 102 m/s2
D. 4 × 1019 m/s2
3. A rectangular book weighing 20 N with sides of 10 cm and 20 cm is placed on a horizontal table. Using each of your hands, you exert forces of 10 N each in opposite directions at opposite corners, such that you are pushing parallel to the shorter side in each case. What net torque are you providing to the book?
A. 0 N-m
B. 0.5 N-m
C. 1 N-m
D. 2 N-m
4. A hammer head with a mass of 500 g moving at 4 m/s collides with a nail (m = 4 g) and comes to a stop in 0.002 seconds. What average force acts on the nail during that time?
A. 106 N
B. 103 N
C. 8 N
D. 8 ×103 N
5. A solid plastic cube with uniform density (side length = 0.5 m) of mass 100 kg is placed in a vat of fluid whose specific gravity is 1.2. What fraction of the cubes volume floats above the surface of the fluid?
A. 1/5
B. 1/3
C. 2/3
D. 4/5
6. An object with mass 30 kg and specific gravity 3.6 is placed in a fluid whose specific gravity is 1.2. Neglecting viscosity, which of the following is true?
A. The acceleration of the object is (1/3)g and its apparent weight is 100N
B. The acceleration of the object is (2/3)g and its apparent weight is 100N
C. The acceleration of the object is (1/3)g and its apparent weight is 200N
D. The acceleration of the object is (2/3)g and its apparent weight is 200N
7. A fluid of density ρ flows through a horizontal pipe with negligible viscosity. The flow is streamline with constant flow rate. The diameter of the pipe at Point 1 is d and the flow speed is v. If the diameter of the pipe at Point 2 is d/3, then the pressure at Point 2 is:
A. Less than the pressure at Point 1 by 4ρv
B. Less than the pressure at Point 1 by 40ρv
C. More than the pressure at Point 1 by 4ρv
D. More than the pressure at Point 1 by 40ρv
8. An ideal fluid flows through a pipe with radius R with flow speed v. If the pipe splits up into three separate paths, each with radius (R/2), what is the flow speed through each of the paths?
A. v/3
B. 2v/3
C. 4v/3
D. 4v
9. Traveling at an initial speed of 1.5 x 106 m/s, a proton enters a region of constant magnetic field of magnitude 1.5 T. If the protons initial velocity vector makes an angle of 30° with the magnetic field, compute the protons speed 4 s after entering the magnetic field.
A. 5.0 × 105 m/s
B. 7.5 × 105 m/s
C. 1.5 × 106 m/s
D. 3.0 × 106 m/s
10. Consider two adjacent transparent media. The speed of light through Medium 1 is v1, and the speed of light through Medium 2 is v2. If v1 < v2, then total internal reflection will occur at the interface between these media if a beam of light is
A. incident in Medium 1 and strikes the interface at an angle of incidence greater than arcsin(v1/v2)
B. incident in Medium 1 and strikes the interface at an angle of incidence greater than arcsin(v2/v1)
C. incident in Medium 2 and strikes the interface at an angle of incidence greater than arcsin(v1/v2)
D. incident in Medium 2 and strikes the interface at an angle of incidence greater than arcsin(v2/v1)
