A high power line carries a current of 1.0 kA. What is the strength of the magnetic field this line produces at the ground, 10 m away? (0 = 4 10-7 T m/A)
A) 4.7 T B) 20 T C) 6.4 T D) 56 T
Question 2
The half-life of cobalt-60 is 5.3 years, while that of strontium-90 is 28 years. Suppose that samples of cobalt-60 and strontium-90 are such that they initially have the same activity (number of decays per second).
What is true about the initial numbers of cobalt-60 and strontium-90 nuclei in these samples?
A) There are more strontium-90 than cobalt-60 nuclei.
B) There are equal numbers of cobalt-60 and strontium-90 nuclei.
C) It is not possible to compare numbers of nuclei without knowing the masses of the samples.
D) There are more cobalt-60 than strontium-90 nuclei.
Use of compass in the field at Sangiran, Java.
functional magnetic resonance imaging
Johannes Gutenberg, Page from the Forty-Two-Line Bible, Mainz.
Scientists do research in the laboratory and in the field
A solenoid has an area of 41.0 cm2. Find the change in magnetic flux through the solenoid.
Physics: Power, Energy and Time