ANSWER:
The study and analysis of light according to its component wavelengths is called spectroscopy.
EXPLANATION:
Spectroscopy is the branch of science that is concerned with the investigation and measurement of spectrum produced when matter interacts with or emits electromagnetic radiation.It helps us to identify atoms and molecules in the object.Spectroscopy is used to find out Dopplers effect (the red shift and blue shift),which tells how fast the object is comming towards earth or moving away from the earth.
Answer:
The velocity of the tennis ball is 4.52 m/s.
Explanation:
Given that,
The distance covered by ball, d = 9.5 meters (due south)
Time, t = 2.1 sec
Let v is the velocity of the tennis ball. We know that the velocity of an object is given by the total distance covered divided by total time taken. It is given by :

So, the velocity of the tennis ball is 4.52 m/s. Hence, this is the required solution.
Answer:
15.5 m/s.
Explanation:
Potential energy of the balloon has been converted to kinetic energy.
potential energy = kinetic energy.
mgh = ½mv².
10* 10* 12= ½ *10 *v²
1200 = 5v²
v²=1200÷5
v=√240
v= 15.49~15.5 m/s.
Answer:
4 ohms
Explanation:
Current = Voltage/resistance
2 = 8/R
2R = 8
R = 4