Answer:
83.67 m/s
Explanation:
Set up a calculation to convert units of measure to what you need.
You have km/s and you need m/s.
4.08km 1000 m 83.67m
----------- X ---------- = --------------- the km will cancel out and you are left
12.0 s 1 km s with m/s
Answer:
300 m
Explanation:
The train accelerate from the rest so u = 0 m/sec
Final speed that is v = 80 m/sec
Time t = 30 sec
The distance traveled by first plane = 1200 m
We know the equation of motion 
where s is distance a is acceleration and u is initial velocity
Using this equation for first plane 
As the acceleration is same for both the plane so a for second plane will be 2.67 
The another equation of motion is 
using this equation for second plane 
s = 300 m
Answer:
The car must be moving away from the person.
Explanation:
From Doppler's Effect, we know that when a sound source moves towards a stationary observer, the apparent frequency of that sound increases. While the apparent frequency decreases if the source moves away from the stationary observer.
The audible range of frequencies for a human ear is 20 Hz to 20000 Hz. Therefore, in order for the sound of a loud speaker to be audible for the person, the frequency must decrease below 20000 Hz.
<u>Due to this reason, the car must be moving away from the person.</u>
Answer:
The answer to your question is when time = 50 s, work = 5000 J
when time = 90 s, work = 9000 J
Explanation:
Data
time = 50 s or 90 s
Power = 100 watts
Power is defined as the rate of work done per unit of time.
Power = Work / time
-Solve for Work
Work = Power x time
-Substitution
Work = 100 x 50
-Result
Work = 5000
2.-When time = 90 s
Work = 100 x 90
-Result
Work = 9000 watts
B is the awser
good luck and hope it helps
