Answer:
option B
Explanation:
given,
Satellite B has an orbital radius nine times that of satellite A.
R' = 9 R
now, orbital velocity of the satellite A
........(1)
now, orbital velocity of satellite B
from equation 1
hence, the correct answer is option B
Answer:
The time taken by the duck to cross the lake is, t= 4 s
Explanation:
Given data,
The initial speed of the ducks, u = 3 m/s
The final speed of the ducks, v = 7 m/s
The acceleration of the duck, a = 1 m/s²
The formula for the acceleration is,
a = (v - u) / t
∴ t = (v - u) / a
Substituting the given values in the above equation,
t = (7 - 3) / 1
= 4 s
Hence, the time taken by the duck to cross the lake is, t= 4 s
Answer:
Three types of electromagnetic waves, used to transmit various information
Explanation:
A form of energy waves having both electric & magnetic fields are Electromagnetic waves. Three types -
Radio Waves - These have longest wavelengths & transmit data through radio, satellites, radar .
Micro Waves - These have shorter wavelengths & are used in cooking appliances & predicting weather.
X rays - These have more short wavelength and can penerate soft tissues like skin & muscle, hence are used for medical examining
Answer: s=d/t= 500/7.0=71.42 m/s
Explanation:
