Answer:
The wavelength will be 4 cm, frequency will be 4.66 Hz and wave speed is 18.6 cm/sec
Explanation:
Given:
No. of crest = 13
No. of trough = 15
Time = 3 seconds
Hence, 1 crest or 1 trough = 
therefore,
13 C + 15 T = 
=
Time given 3 seconds
= 

2 cm distance is travelled is time period

Again wave will travel in 1 T = 4 cm
wave speed v =
= 
= 18.6 cm/s
A protostar reaches equilibrium when gravity is balanced by the outward force of nuclear fusion.
Explanation:
The acceleration g varies by about 1/2 of 1 percent with position on Earth's surface, from about 9.78 metres per second per second at the Equator to approximately 9.83 metres per second per second at the poles.
Answer:
η = 58.8%
Explanation:
Work is defined as the force applied by the distance traveled by the body.

where:
W = work [J] (units of joules)
F = force = 294 [N]
d = distance = 5 [m]
![W = 294*5\\W = 1470 [J]\\](https://tex.z-dn.net/?f=W%20%3D%20294%2A5%5C%5CW%20%3D%201470%20%5BJ%5D%5C%5C)
Efficiency is defined as the energy required to perform an activity in relation to the energy actually added to perform some activity. This can be better understood by means of the following equation.

I dont know but i know i dont lnow if this is true but the gravity is slowly going away every 4 year i dont know i think.