Earth and other planets closest to the sun are mostly made of ? A) Rocks
B) Metal
C) Water
D) Gas

Match each type of lever with the correct diagram. 1. first-class 2. third-class 3. second-class

How can you measure the amplitude of a longitudinal wave?

Estimate the kinetic energy of mars with respect to the sun as the sum of two terms, that due to its daily rotation about its axis, and that due to its yearly revolution about the sun. (assume mars is a uniform sphere with mass = 6.4×10 to the power of 23 kg, radius = 3.4×10 to the power of 6 m, rotation period = 24.7 hours, orbital period = 686 days and is 2.3×10 to the power of 8 km from the sun.)