Mars' magnetic field is so weak because

A) it spins much slower than Earth does.
B) it core may no longer be molten.
C) its core contains less iron than our own.
D) Both B and C are probable.
E) All of the above are correct.


D

Physics & Space Science

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A cable is 100 m long, has a cross-sectional area of 1.0 mm2, and is made of a material having a Young's modulus of 1.0 × 1011 N/m2. If a 1000-N force is applied to stretch the cable, how far does it stretch?

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Physics & Space Science

A magician can make a candle look as if it is burning under water by focusing light from a candle flame burning in air directly on top of an underwater candle. To do this you want to use a (Hint: eliminate those that cannot work.)

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Physics & Space Science

An object of mass m moving with a certain speed has a kinetic energy of 0.0124 J. The object collides with a horizontal spring and compresses it by 0.800 m before it is brought to rest. What is the spring constant of this spring?

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Physics & Space Science