The statemengt is <em>false</em>. Electromgnetic waves do not require a medium to transfer energy. They can transfer energy through vacuum (empty space with nothing in it). If electrimagnetic waves needed a medium to move through from place to place, then we could never see the sun, and also it would get very cold here.
Answer:
Clockwise and counter clockwises, depands.
Explanation:
The direction of current in a loop of wire in a magnatic field depands on the direction in which the loop is moved and the applied magnatic field.
this is determined by what is called right hand rule.
I will give one scenario, let's say that the loop is moved upwards and the applied magnatic field is into the page (if you drew the loop in 2D on a piece of paper), in this case the direction would be clockwise.
Answer:
a. Mass number is the sum of number of protons and neutrons present in the nucleus of an atom.
A = p + n
Charge is a unit of matter that tells how more or less the number of electrons are present as compared to number of protons in an atom. A positive charge means the atom lacks electrons.
Gamma rays are highly energetic electromagnetic rays. They have high penetrating power and are very difficult to shield owing to high energy.
b. The compete nuclear equation is:

This is a alpha decay process because alpha particle which is Helium atom is being produced. Francium is being formed after alpha particle is emitted.
c. The complete nuclear reaction is:

This is a positron emission process where in Rubidium is being formed.
Answer:
1,632 rounded by the nearest ten is 1630
783 rounded by the nearest hundred is 800
43,761 rounded by the nearest thousand is 44,00
Explanation:
Redox reactions involve the gain or loss of C. electrons