A piano wire has a radius of 0.50 mm. One end is fixed and the other is wrapped around a tuning peg, which has a diameter of 3.5 mm and is 80 cm away. After the wire just becomes taut, the peg is given three full turns
What is the tension in the wire? Young's modulus for steel is 20 × 1010 N/m2. A) 3.8 kN
B) 4.3 kN
C) 6.5 kN
D) 8.7 kN
E) 9.8 kN
C
You might also like to view...
Is it possible for a system to have negative potential energy?
A) Yes, as long as the kinetic energy is positive. B) Yes, as long as the total energy is positive. C) Yes, since the choice of the zero of potential energy is arbitrary. D) No, because the kinetic energy of a system must equal its potential energy. E) No, because this would have no physical meaning.
Force on a Moving Charge: A proton moving eastward with a velocity of 5.0 km/s enters a magnetic field of 0.20 T pointing northward. What are the magnitude and direction of the force that the magnetic field exerts on the proton? (e = 1.60 × 10-19 C)
A. 0 N B. 1.6 × 10-16 N upwards C. 1.6 × 10-16 N downwards D. 1.1 × 10-16 N eastwards E. 4.4 × 10-16 N westwards
What is the observational difference between Types I & II supernovae?
A: Ia's come from white dwarfs in binaries whereas II's come from dying massive stars B: I's are brighter than II's C: I's are fainter than II's D: I's are Hydrogen poor while II's are Hydrogen rich E: I's have no central remnant while II's have neutron stars
Why do astronomers believe supermassive black holes are the source of an AGN's energy?
a. Such black holes have been found at the center of most galaxies both active and inactive. b. Radio jets are seen from low mass black holes plus accretion disks inside our galaxy. c. jets and accretion disks have been observed in active galaxies d. black holes can produce so much energy in such a small place. e. all of the above