Answer:
The oldest stars in spiral galaxies are younger than the oldest stars in elliptical galaxies.
Explanation:
Spiral galaxies have a greater star formation than elliptical galaxies, since the latter contain less gas and dust. Therefore, the rate of creation of new stars is lower in elliptical galaxies. These galaxies are dominated by old stars, with a long evolution. While the spiral galaxies have stars with a faster evolution.
Answer:
True.
Explanation:
A diode, which allows current to flow in one direction only, consists of two types of semiconductors joined together.
A semiconductor can be defined as a crystalline solid substance that has its conductivity lying between that of a metal and an insulator, due to the effects of temperature or an addition of an impurity. Semiconductors are classified into two main categories;
1. Extrinsic semiconductor.
2. Intrinsic semiconductor.
An intrinsic semiconductor is a crystalline solid substance that is in its purest form and having no impurities added to it. Examples of intrinsic semiconductor are Germanium and Silicon.
In an intrinsic semiconductor, the number of free electrons is equal to the number of holes. Also, in an intrinsic semiconductor the number of holes and free electrons is directly proportional to the temperature; as the temperature increases, the number of holes and free electrons increases and vice-versa.
In an intrinsic semiconductor, each free electrons (valence electrons) produces a covalent bond.
you can increase kinetic thermal energy of the water by boiling it.
Answer:
C. (100+4.9)m
Explanation:
u = 100m/s, t = 1 sec, g = 9.8m/s^2
s = ut + 1/2gt^2
s = 100×1 + 1/2×9.8×1^2 = 100+4.9
s = (100+4.9)m
Answer:
v0 = 24.42 m/s (Approx)
Explanation:
Given:
Increase in frequency = 7.1% =
Computation:
Assume n = 100%
n1 = [(v+v0)/(v+v1)]n
[100 + 7.1] = [(344+v0)/(344+0)]100
107.1 = [(344+v0)/(344)]100
v0 = 24.42 m/s (Approx)