Answer:
electrostatics
gravitational forces
Explanation:
rubbing the ballon leads to it acquiring charges that are opposite to that in the wall.the electostatic forces attract the ballon to the wall and tyhe gravitational pull later acts on the ballon causing it to fall down
Answer:
Democritus
Explanation:
He called these "uncuttable" pieces atomos. This is where the modern term atom comes from. Democritus first introduced the idea of the atom almost 2500 years ago.
Answer:
A) 0.50 mV
Explanation:
In this problem, we can think the wings of the bird as a metal rod moving across a magnetic field. So, and emf will be induced into the wings of the bird, according to the formula:

where
is the strength of the magnetic field
v = 13 m/s is the speed of the bird
L = 1.2 m is the wingspan of the bird
is the angle between the direction of motion and the direction of the magnetic field
Substituting numbers into the formula, we find

The size has gotten smaller, they last longer, easier to carry around, safer, etc