Explanation:
A wave is a disturbance in a medium. For example, when some pebbles are thrown in water, the water particles gets disturbed. A wave is characterized by the following parameters i.e.
Frequency
Wavelength etc
The number of oscillations or vibrations in a medium is called the frequency of a wave.
Also, the distance between two consecutive crests and troughs is called the wavelength of a wave. The relationship between the wavelength and the frequency of a wave is given by :
Speed of wave = frequency × wavelength
you could make a self propelled car all you need is cardboard, wheels, and a balloons or rubber bands
Answer:
Ohms law
Explanation:
Which states that the current flowing through any cross-section of the conductor is directly proportional to the potential differenceapplied across its end, provided physical conditions like temperature and pressure remain constant.
Answer:
b) The star is moving away from us.
Explanation:
If an object moves toward us, the light waves it emits are compressed - the wavelength of the light will be shorter, making the light bluer. On the other hand, if an object moves away from us, the light waves are stretched, making it redder. If from laboratory measurements we know that a specific hydrogen spectral line appears at the wavelength of 121.6 nanometers (nm) and the spectrum of a particular star shows the same hydrogen line appearing at the wavelength of 121.8 nm, we can conclude that the star is moving away from npos, since the wavelength related to that star is more expanded.
Answer:
Speed of the speeder will be 28 m/sec
Explanation:
In first case police car is traveling with a speed of 90 km/hr
We can change 90 km/hr in m/sec
So 
Car is traveling for 1 sec with a constant speed so distance traveled in 1 sec = 25×1 = 25 m
After that car is accelerating with 
for 7 sec
So distance traveled by car in these 7 sec
So total distance traveled by police car = 224 m
This distance is also same for speeder
Now let speeder is moving with constant velocity v
so 
v = 28 m/sec
