Answer:
C. At a particular instant
Explanation:
Speed is the defined as the ratio between the distance covered by an object and the time taken:
where d is the distance and t the time.
However, there are two possible measurements of speed:
- Average speed: this is the speed measured over a non-zero time interval (for example: a car moving 100 metres in 5 seconds; its average speed is
- Instantaneous speed: this is the speed of an object measured at a particular instant in time, so for a time interval that tends to zero. So, in the previous example, the average speed is 20 m/s but the instantaneous speed of the car at various instants of time can be different from that value.
Explanation:
The frequency of radio waves is 1.667 GHz
One portion of the same wave front travels 1.260 mm farther than the other before the two signals are combined.
There are two conditions for interference either constructive or destructive.
For constructive interference , the path difference is n times of wavelength and for destructive interference, the path difference is (n+1/2) times of wavelength
We can find wavelength in this case as follows :
If we divide path difference by wavelength,
It means that the path difference is 7 times of the wavelength. it means the two waves combine constructively and the value of m for the path difference between the two signals is 7.
Density=mass/volume therefore volume=mass/density; 55g/11.4g/cm^3= 4.82cm^3
Answer:
7 meters, 2.8 meters
Explanation:
work done (nm) = force (n) * distance (m)
140= 20 * m
140/20 = m
m=7 meters
140= 50 * m
140/50 = m
m= 2.8 meters
