<h2>QUESTION:- </h2>
➜what is kepler's law??
Kepler gave the three laws or theorems of motion of the orbitals bodies
This law state that the celestial bodies revolves around the stars in elliptical orbit and star as a single focus.
Example :- Earth revolves around the Sun as assuming it as single focus
This also shows that earth revolves around the sun in elliptical orbit.
Area covered by the planet is equal in equal duration of time irrespective of the position of the planet.
It also states that Angular momentum is constant
As Angular momentum is constant it means areal velocity is also constant.
where:-
A is the area.
T is the time.
L is the angular momentum.
M is the mass of the body.
square of the time of the revolution is directly proportional to the cube of the distance between the planet and star in Astronomical unit.
where:-
T = time of revolution
a is the distance between the planet and star.
Some benefits to solar power:
Isolated power is very abundant on earth.
Is very sustainable (5 billion years of good use)
Eco friendly excluding panel production.
Some disadvantages:
Very expensive to set up
Takes up a lot of space per person
Requires exotic materials to construct
Energy storage is difficult with solar cells compared to fossil fuels.
The answer is A. Friction.
Friction is the resisting force between two objects that move against one another.
Hope this helps! :)
Answer:
B. -900 kg-m/s2
Explanation:
First of all, we need to calculate the acceleration of the hockey player, which is given by:
where
v = 12 m/s is the final speed
u = 18 m/s is the initial speed
t = 0.6 s is the time
Substituting into the formula, we find
And now we can calculate the force exerted by using Newton's second law:
where m=90 kg is the mass of the hockey player. Substituting into the formula, we find
Answer:
-47 °C
Explanation:
Speed of sound in air at sea level is:
v = 331 m/s + 0.6 m/s/°C T
where T is the temperature in Celsius.
The speed of sound is also the frequency times the wavelength:
v = fλ
Therefore:
fλ = 331 m/s + 0.6 m/s/°C T
(658 Hz) (0.46 m) = 331 m/s + 0.6 m/s/°C T
302.68 m/s = 331 m/s + 0.6 m/s/°C T
-28.32 m/s = 0.6 m/s/°C T
T = -47.2 °C
Rounding to two significant figures, the temperature is -47 °C.
