Push and pull force of motion
Answer:
Explanation:
It is given that,
Wavelength of hydrogen line,
Shift in wavelength,
According to Relativistic Doppler Effect, the shift in wavelength is given by :
v is the speed of star
c is the speed of light
or
v = 91.43 km/s
So, the star is moving with a speed of about 100 km/s. Hence, this is the required solution.
Answer:
net force= 2000-1000=1000
a=v-u/t=5/20=1/4
m=?
m=f/a
=1000÷1/4=4000kg
all engines operate at less than 100 percent efficiency because they EMIT heat. ;)