Answer:
it increases by a factor 1.07
Explanation:
The peak wavelength of an object is given by Wien's displacement law:
(1)
where
b is the Wien's displacement constant
T is the temperature (in Kelvins) of the object
given the relationship between frequency and wavelength of an electromagnetic wave:
where c is the speed of light, we can rewrite (1) as
So the peak frequency is directly proportional to the temperature in Kelvin.
In this problem, the temperature of the object changes from
to
so the peak frequency changes by a factor
<span>As it is uniform circular motion therefore speed is constant. Therefore we can rule out option B. Also in circular motion the direction of velocity vector changes therefore velocity can't be constant. Therefore option B is incorrect as well. Also centripetal acceleration is always towards the center so option D is wrong as well.
That implies
option A is correct.</span>
Answer:
a) r = 4.22 10⁷ m, b) v = 3.07 10³ m / s and c) a = 0.224 m / s²
Explanation:
a) For this exercise we will use Newton's second law where acceleration is centripetal and force is gravitational force
F = m a
a = v² / r
F = G m M / r²
G m M / r² = m v² / r
G M / r = v²
The squared velocity is a scalar and this value is constant, so let's use the uniform motion relationships
v = d / t
As the orbit is circular the distance is the length of the circle in 24 h time
d = 2π r
t = 24 h (3600 s / 1 h) = 86400 s
Let's replace
G M / r = (2π r / t)²
G M = 4 π² r³ / t²
r = ∛(G M t² / (4π²)
r = ∛( 6.67 10⁻¹¹ 5.98 10²⁴ 86400² / (4π²)) = ∛( 75.4 10²¹)
r = 4.22 10⁷ m
b) the speed module is
v = √G M / r
v = √(6.67 10⁻¹¹ 5.98 10²⁴/ 4.22 10⁷
v = 3.07 10³ m / s
c) the acceleration is
a = G M / r²
a = 6.67 10⁻¹¹ 5.98 10²⁴ / (4.22 10⁷)²
a = 0.224 m / s²
Answer: In an exothermic reaction, the products have less energy than the reactants.
Explanation: There are two types of reactions:
1. Endothermic reactions: These are the reactions in which energy is required in the reaction. The energy of the products are more than the energy of the reactants.
2. Exothermic reactions: These are the reactions in which energy is released in the reaction. The energy of the products is less than the energy of the reactants.
Hence, in an exothermic reaction, the products have less energy than the reactants.
