Answer all for full points what is gravity? what are the three types of contact forces and what is an example of each? how are electricity and magnets connected? what is the difference between a balanced and an unbalanced force? give an example of each. what are si units, and why are they used?

True or false when elements combine to form a mixture, the resulting chemical properties may be very different from those of the elements that make it.

Afaulty model rocket moves in the xy-plane (the positive y direction is vertically upward). the rocket's acceleration has components ax(t) = ? t2 and ay(t) = ? ? ? t, where ? = 2.50 m/s4 , ? = 9.00 m/s2 , and ? = 1.40 m/s3 . at t = 0 the rocket is at the origin and has velocity ~v0 = v0x ? i + v0y ? j with v0x = 1.00 m/s and v0y = 7.00 m/s. (a) calculate the velocity and position vectors as functions of time. (b) what is the maximum height reached by the rocket? (c) sketch the path of the rocket. (d) what is the horizontal displacement of the rocket when it returns to y = 0?

Blank is the perceived frequency of a sound wave