Answer:
Option (d) is correct.
Explanation:
Work done is given by :
W = Fd, where F is force and d is displacement
Unit of work done :
The SI unit of force is Newton (N) and that of displacement is meter (m). So, the unit of work done is N-m. It is call Joule. It means that the unit of work done is Joule.
Power is given by rate at which the work is done. It is given by :
P = W/t, W is work done and t is time
Unit of power:
Unit of work is Joule (J) and that of time is second (s). It means that the unit of power is Watt and it is equal to Joule/second
Hence, the correct option is (d) "The unit for work is a joule. The unit for power is a watt, which is a joule per second".
In a longitudinal wave, the motion of the medium is parrellel to the direction of the wave.
Answer:
1000 kg
Explanation:
Force = mass x acceleration, Hence, mass = Force/acceleration
mass = 4000/4 = 1000 kg
Answer:
<em>The canyon is approximately 314 meters away</em>
Explanation:
<u>Speed of Sound</u>
If we emit sounds in an open space where a large obstacle (like a mountain) is expected to return the sounds, then it will travel forth and back at a given speed for a certain time. We can assume the speed of sound is constant, so we could know the approximate distance of the mountain (or canyon in our case) by the known formula.
Where 
is the speed of sound and t is half the time we hear our echo.
The speed of sound in m/s can be calculated from the approximate formula in terms of the temperature T in degrees Celsius
We have 
, so
Let's compute x, for t=1.8/2=0.9 seconds
The canyon is approximately 314 meters away
Answer:
c) main sequence, supergiant, supernova, black hole
