Answer:
B. 500 years
Explanation:
The light coming from the star and reaching us on the Earth travels with uniform motion (with constant velocity), so we can use the equation of uniform motion which relates distance covered, speed and time taken:
where
v is the speed
d is the distance covered
t is the time taken
In this problem:
is the speed at which light travels
is the distance that light has to cover from the star to the Earth
Therefore, by rearranging the equation, we can find the time:
And by converting into years, this time is
So, approximately 500 years: this means that the image we see of the star is 500 years old.
Yes it is consider biology
Answer:
B
Explanation:
the balloon has a negative charge and the metal sphere has a positive charge
Answer:
a) 3-in. pipe
Explanation:
Given that
Fluid flow is in same amount in the same time it means that volume flow rate is same for the pipes
Volume flow rate
Q = A V
A=Area ,V=Velocity
If diameter d is more then the velocity will be less for same volume flow rate .We also Know that if pressure is more then the velocity will be less.
The second pipe 3 in diameter having more diameter then the velocity will be less but the pressure will be more.
That is why the 3 in diameter is having more pressure than 2 in diameter pipe.
Therefore the answer will be a.
a) 3-in diameter pipe
Answer:
a) 0 m/s
b) 4 m/s
Explanation:
The average velocity would end up being 0 because it is displacement over time and the displacement here is 0. However, speed is total distance over time which here is 400/100 so it is 4.
