Answer:
Use specific tools built specifically for that specific measurement.
Explanation:
Answer:
15.67 m/s
Explanation:
The ball has a projectile motion, with a horizontal uniform motion with constant speed and a vertical accelerated motion with constant acceleration g=9.8 m/s^2 downward.
Let's consider the vertical motion only first: the vertical distance covered by the ball, which is S=50 m, is given by

where t is the time of the fall. Substituting S=50 m and re-arranging the equation, we can find t:

Now we now that the ball must cover a distance of 50 meters horizontally during this time, in order to fall inside the carriage; therefore, the velocity of the carriage should be:

Answer:
v = 8.4 m/s
Explanation:
The question ays, "A longitudinal wave has a frequency of 200 Hz and a wavelength of 4.2m. What is the speed of the wave?".
Frequency of a wave, f = 200 Hz
Wavelength = 4.2 cm = 0.042 m
We need to find the speed of the wave. The formula for the speed of a wave is given by :

So, the speed of the wave is equal to 8.4 m/s.
Answer:
Constructive interference
Explanation:
Here, the medium is same, same wavelength, same frequency, same amplitude and same direction of propagation.
Let the intensity of waves be I which is same for both
The formula for the net intensity is

where, Ф be the phase difference
So, 
Here, IR is maximum so the interference is constructive in nature.
Answer:
Explanation:
The properties of magnets are used to make electricity. Moving magnetic fields pull and push electrons. ... Moving a magnet around a coil of wire, or moving a coil of wire around a magnet, pushes the electrons in the wire and creates an electrical current.