Answer:
Explanation:
Electron's kinetic energy = 2 eV
= 2 x 1.6 x 10⁻¹⁹ J
1/2 m v² = 3.2 x 10⁻¹⁹
1/2 x 9.1 x 10⁻³¹ x v² = 3.2 x 10⁻¹⁹
v² = .703 x 10¹²
v = .8385 x 10⁶ m/s
Electrons revolve in a circular orbit when forced to travel in a magnetic field whose radius can be expressed as follows
r = mv / Bq
where m , v and q are mass , velocity and charge of electron .
here given magnetic field B = 90 mT
= 90 x 10⁻³ T
Putting these values in the expression above
r = mv / Bq
= 
= .052 mm.
Answer:
Temperature is also a condition that affects the speed of sound. Heat, like sound, is a form of kinetic energy. Molecules at higher temperatures have more energy, thus they can vibrate faster. Since the molecules vibrate faster, sound waves can travel more quickly.
Answer:
Option (D)
Explanation:
Terrestrial planets refers to those four planets that are nearest to the sun and that lies within the asteroid belt. These planets are mainly composed of rocks or other metal objects that have a hard and resistant surface on it. They have a metal core that is molten (liquid) in nature, and atmosphere is relatively less dense, and also various geological features are present on it like the crater, volcanoes which can be observed with the help of satellites. The average densities of these planets is about four times the density of water. For example, the density of water is 1 g/cm³, whereas the density of earth is 5.5 g/cm³.
Thus, the correct answer is option (D).
Yes, atoms need to be equal in protons and electrons
