Answer: Electromagnetic waves (Ultraviolet light, between 100 nm and 380 nm)
Explanation:
Solar cells work by the photoelectric effect, which consists of the emission of electrons (electric current) when light (electromagnetic waves) falls on a metal surface under certain conditions.
In this sense, the portion of the electromagnetic spectrum this cells use is Ultraviolet light (UV) from the Sun, whose wavelength is approximately between 100 nm and 380 nm.
It is important to note, this is a type of electromagnetic radiation that is not visible to the human eye.
An intense solar storm COULD disrupt communications and damage the power grid. <em> (A)</em>
Answer:
Explanation:
given
T = 3months = 7.9 × 10⁶s
orbital speed = 88 × 10³m/s
V= 2πr÷T
∴ r = (V×T) ÷ 2π
r = (88km × 7.9 × 10⁶s) ÷ 2π
r = 1.10 × 10⁸km
using kepler's 3rd law
mass of both stars = (seperation diatance)³/(orbital speed)²
M₁ + M₂ = (2r)³/(
year)²
= (1.06 × 10²⁵)/(6.2×10¹³)
1.71×10¹²kg
since M₁ = M₂ =1.71×10¹²kg ÷ 2
M₁ = M₂ = 8.55×10¹¹kg
Answer:
Explanation:
Stored energy in spring = 1/2 k x² , k is spring constant , x is compression.
= 1/2 x 8 x (5.7 x 10⁻²)²
= 129.96 x 10⁻⁴ J
Energy lost due to friction = force x distance
= .035 x .17
= .00595 J
Energy used in providing kinetic energy to projectile.
129.96 x 10⁻⁴ - .00595
.012996 - .00595
= .007046 J
So
1/2 m v² = .007046
v² = .007046 x 2 / .0059
= 2.3885
v = 1.545 m /s
